diff --git a/src/main/java/org/luaj/vm3/lib/StringLib.java b/src/main/java/org/luaj/vm3/lib/StringLib.java
index 317d68920..afde5979b 100644
--- a/src/main/java/org/luaj/vm3/lib/StringLib.java
+++ b/src/main/java/org/luaj/vm3/lib/StringLib.java
@@ -1155,7 +1155,7 @@ public class StringLib extends TwoArgFunction {
 			if ( poff == plen || poff + 1 == plen ) {
 				error( "unbalanced pattern" );
 			}
-			if ( s.luaByte( soff ) != p.luaByte( poff ) )
+			if ( soff >= s.length() || s.luaByte( soff ) != p.luaByte( poff ) )
 				return -1;
 			else {
 				int b = p.luaByte( poff );
diff --git a/src/main/resources/assets/opencomputers/lang/de_DE.lang b/src/main/resources/assets/opencomputers/lang/de_DE.lang
index c9f1bc053..2b7bc3535 100644
--- a/src/main/resources/assets/opencomputers/lang/de_DE.lang
+++ b/src/main/resources/assets/opencomputers/lang/de_DE.lang
@@ -12,6 +12,7 @@ oc:tile.Case2.name=Computergehäuse (Stufe 3)
 oc:tile.Charger.name=Ladestation
 oc:tile.DiskDrive.name=Diskettenlaufwerk
 oc:tile.Keyboard.name=Tastatur
+oc:tile.Hologram.name=Hologrammprojektor
 oc:tile.PowerConverter.name=Leistungswandler
 oc:tile.PowerDistributor.name=Stromverteiler
 oc:tile.Redstone.name=Redstone-I/O
@@ -136,6 +137,7 @@ oc:tooltip.GraphicsCard=Erlaubt es, den angezeigten Inhalt von Bildschirmen zu 
 oc:tooltip.InternetCard=Diese Karte erlaubt es, HTTP-Anfragen zu senden und echte TCP Sockets zu verwenden.
 oc:tooltip.IronNugget=Ein Nugget, das aus Eisen besteht, darum wird es ja auch Eisennugget genannt, duh...
 oc:tooltip.Keyboard=Kann an Bildschirmen befestigt werden, um auf ihnen zu tippen.
+oc:tooltip.Hologram=Ein Volumendisplay das beliebige, von Computern festgelegte Voxelstrukturen anzeigt.[nl] Auflösung: §f48x32x48§7. [nl] Farbtiefe: §fMonochrom§7.
 oc:tooltip.Memory=Braucht ein jeder Computer, um zu starten. Je mehr vorhanden, desto komplexere Programme können ausgeführt werden.
 oc:tooltip.Microchip=Tritt auch unter dem Alias Integrierter Schaltkreis auf. Keine Ahnung, warum das auch mit Redstone klappt, aber es funktioniert.
 oc:tooltip.NetworkCard=Erlaubt es Computern, die über mehrere Blöcke miteinander verbunden sind (z.B. Kabel), mittels Netzwerknachrichten zu kommunizieren.
diff --git a/src/main/resources/assets/opencomputers/lang/en_US.lang b/src/main/resources/assets/opencomputers/lang/en_US.lang
index b5f8195d6..a1d56e273 100644
--- a/src/main/resources/assets/opencomputers/lang/en_US.lang
+++ b/src/main/resources/assets/opencomputers/lang/en_US.lang
@@ -12,6 +12,7 @@ oc:tile.Case2.name=Computer Case (Tier 3)
 oc:tile.Charger.name=Charger
 oc:tile.DiskDrive.name=Disk Drive
 oc:tile.Keyboard.name=Keyboard
+oc:tile.Hologram.name=Hologram Projector
 oc:tile.PowerConverter.name=Power Converter
 oc:tile.PowerDistributor.name=Power Distributor
 oc:tile.Redstone.name=Redstone I/O
@@ -136,6 +137,7 @@ oc:tooltip.GraphicsCard=Used to change what's displayed on screens.[nl] Maximum
 oc:tooltip.InternetCard=This card allows making HTTP requests and using real TCP sockets.
 oc:tooltip.IronNugget=A nugget made of iron, that's why it's called an Iron Nugget, duh...
 oc:tooltip.Keyboard=Can be attached to screens to allow typing on them.
+oc:tooltip.Hologram=A volumetric display that can be controlled by computers to display arbitrary voxel structures.[nl] Resolution: §f48x32x48§7. [nl] Color depth: §fMonochrome§7.
 oc:tooltip.Memory=Required to get computers to run. The more you have, the more complex the programs you can run.
 oc:tooltip.Microchip=The chip formerly known as Integrated Circuit. I have no idea why this works with redstone, but it does.
 oc:tooltip.NetworkCard=Allows distant computers connected by other blocks (such as cable) to communicate by sending messages to each other.
diff --git a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
index ebba420c7..5eddd65bb 100644
--- a/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
+++ b/src/main/resources/assets/opencomputers/lua/component/internet/bin/irc.lua
@@ -41,12 +41,8 @@ end
 
 -- utility method for reply tracking tables.
 function autocreate(table, key)
-  local value = rawget(table, key)
-  if not value then
-    value = {}
-    rawset(table, key, value)
-  end
-  return value
+  table[key] = {}
+  return table[key]
 end
 
 -- extract nickname from identity.
@@ -172,36 +168,36 @@ local function handleCommand(prefix, command, args, message)
     print(message)
   elseif command == commands.RPL_WHOISUSER then
     local nick = args[2]:lower()
-    whois[nick].nick = nick
+    whois[nick].nick = args[2]
     whois[nick].user = args[3]
     whois[nick].host = args[4]
     whois[nick].realName = message
   elseif command == commands.RPL_WHOISSERVER then
-    local nick = args[2]
+    local nick = args[2]:lower()
     whois[nick].server = args[3]
     whois[nick].serverInfo = message
   elseif command == commands.RPL_WHOISOPERATOR then
-    local nick = args[2]
+    local nick = args[2]:lower()
     whois[nick].isOperator = true
   elseif command == commands.RPL_WHOISIDLE then
-    local nick = args[2]
+    local nick = args[2]:lower()
     whois[nick].idle = tonumber(args[3])
   elseif command == commands.RPL_ENDOFWHOIS then
-    local nick = args[2]
+    local nick = args[2]:lower()
     local info = whois[nick]
-    print("Nick: " .. info.nick)
-    print("User name: " .. info.user)
-    print("Real name: " .. info.realName)
-    print("Host: " .. info.host)
-    print("Server: " .. info.server .. "(" .. info.serverInfo .. ")")
-    print("Channels: " .. info.channels)
-    print("Idle for: " .. info.idle)
+    if info.nick then print("Nick: " .. info.nick) end
+    if info.user then print("User name: " .. info.user) end
+    if info.realName then print("Real name: " .. info.realName) end
+    if info.host then print("Host: " .. info.host) end
+    if info.server then print("Server: " .. info.server .. (info.serverInfo and (" (" .. info.serverInfo .. ")") or "")) end
+    if info.channels then print("Channels: " .. info.channels) end
+    if info.idle then print("Idle for: " .. info.idle) end
     whois[nick] = nil
   elseif command == commands.RPL_WHOISCHANNELS then
-    local nick = args[1]
+    local nick = args[2]:lower()
     whois[nick].channels = message
   elseif command == commands.RPL_CHANNELMODEIS then
-    print("Channel mode for " .. args[1] .. ": " .. args[2] .. "(" .. args[3] .. ")")
+    print("Channel mode for " .. args[1] .. ": " .. args[2] .. " (" .. args[3] .. ")")
   elseif command == commands.RPL_NOTOPIC then
     print("No topic is set for " .. args[1] .. ".")
   elseif command == commands.RPL_TOPIC then
@@ -310,7 +306,9 @@ local result, reason = pcall(function()
       print("[" .. (target or "?") .. "] me: " .. line, true)
       if line:lower():sub(1, 5) == "/msg " then
         local user, message = line:sub(6):match("^(%S+) (.+)$")
-        message = text.trim(message)
+        if message then
+          message = text.trim(message)
+        end
         if not user or not message or message == "" then
           print("Invalid use of /msg. Usage: /msg nick|channel message.")
           line = ""
@@ -342,7 +340,7 @@ local result, reason = pcall(function()
             print("Error: " .. tostring(reason))
           elseif type(reason) == "function" then
             callback = reason
-          else
+          elseif reason then
             line = tostring(reason)
           end
         end
@@ -368,7 +366,9 @@ if sock then
   sock:write("QUIT\r\n")
   sock:close()
 end
-event.cancel(timer)
+if timer then
+  event.cancel(timer)
+end
 
 if not result then
   error(reason, 0)
diff --git a/src/main/resources/assets/opencomputers/lua/kernel.lua b/src/main/resources/assets/opencomputers/lua/kernel.lua
index baec22ae5..cc9946c26 100644
--- a/src/main/resources/assets/opencomputers/lua/kernel.lua
+++ b/src/main/resources/assets/opencomputers/lua/kernel.lua
@@ -1,5 +1,5 @@
 local hookInterval = 100
-local deadline = 0
+local deadline = math.huge
 local function checkDeadline()
   if computer.realTime() > deadline then
     debug.sethook(coroutine.running(), checkDeadline, "", 1)
@@ -91,7 +91,11 @@ sandbox = {
   loadfile = nil, -- in boot/*_base.lua
   next = next,
   pairs = pairs,
-  pcall = pcall,
+  pcall = function(...)
+    local result = table.pack(pcall(...))
+    checkDeadline()
+    return table.unpack(result, 1, result.n)
+  end,
   print = nil, -- in boot/*_base.lua
   rawequal = rawequal,
   rawget = rawget,
@@ -103,7 +107,11 @@ sandbox = {
   tostring = tostring,
   type = type,
   _VERSION = "Lua 5.2",
-  xpcall = xpcall,
+  xpcall = function(...)
+    local result = table.pack(xpcall(...))
+    checkDeadline()
+    return table.unpack(result, 1, result.n)
+  end,
 
   coroutine = {
     create = function(f)
diff --git a/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua b/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua
index 2ec7094d8..342f9f04b 100644
--- a/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua
+++ b/src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua
@@ -121,7 +121,7 @@ if #args == 0 and (io.input() == io.stdin or options.i) and not options.c then
       elseif command ~= "" then
         local result, reason = execute(command)
         if not result then
-          io.stderr:write(reason .. "\n")
+          io.stderr:write((tostring(reason) or "unknown error").. "\n")
         elseif term.getCursor() > 1 then
           term.write("\n")
         end
diff --git a/src/main/resources/assets/opencomputers/lua/rom/init.lua b/src/main/resources/assets/opencomputers/lua/rom/init.lua
index 48cc1be29..99afa57f3 100644
--- a/src/main/resources/assets/opencomputers/lua/rom/init.lua
+++ b/src/main/resources/assets/opencomputers/lua/rom/init.lua
@@ -13,8 +13,9 @@ while true do
   io.write(_OSVERSION .. " (" .. math.floor(computer.totalMemory() / 1024) .. "k RAM)\n")
   local result, reason = os.execute(os.getenv("SHELL") .. " -")
   if not result then
-    io.stderr:write((reason or "unknown error") .. "\n")
+    io.stderr:write((tostring(reason) or "unknown error") .. "\n")
     print("Press any key to continue.")
+    os.sleep(0.5)
     event.pull("key")
   end
 end
\ No newline at end of file
diff --git a/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua b/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua
index 111097326..67a5f98d8 100644
--- a/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua
+++ b/src/main/resources/assets/opencomputers/lua/rom/lib/term.lua
@@ -338,7 +338,7 @@ function term.write(value, wrap)
   end
   local blink = term.getCursorBlink()
   term.setCursorBlink(false)
-  local line, nl = value
+  local line, nl
   repeat
     local wrapAfter, margin = math.huge, math.huge
     if wrap then
@@ -356,7 +356,7 @@ function term.write(value, wrap)
       component.gpu.fill(1, h, w, 1, " ")
       cursorY = h
     end
-  until not wrap or not value
+  until not value
   term.setCursorBlink(blink)
 end
 
diff --git a/src/main/resources/assets/opencomputers/recipes/default.recipes b/src/main/resources/assets/opencomputers/recipes/default.recipes
index e901711bb..8534bb21f 100644
--- a/src/main/resources/assets/opencomputers/recipes/default.recipes
+++ b/src/main/resources/assets/opencomputers/recipes/default.recipes
@@ -271,7 +271,7 @@ powerDistributor {
 rack {
   input: [["oc:circuitTier2", "oc:componentCardWLan", "oc:circuitTier2"]
           [fenceIron, chest, fenceIron]
-          ["oc:craftingRouter", "oc:craftingCircuitBoardPrinted","oc:craftingPowerDistributor"]]
+          ["oc:craftingRouter", "oc:craftingCircuitBoardPrinted", "oc:craftingPowerDistributor"]]
 }
 redstone {
   input: [[ingotIron, blockRedstone, ingotIron]
@@ -302,4 +302,9 @@ screen3 {
   input: [[obsidian, yellowDust, obsidian]
           [yellowDust, "oc:circuitTier3", glass]
           [obsidian, yellowDust, obsidian]]
+}
+hologram {
+  input: [[obsidian, glass, obsidian]
+          ["oc:craftingCircuitBoardPrinted", diamond, "oc:craftingCircuitBoardPrinted"]
+          ["oc:circuitTier3", blazeRod, "oc:circuitTier3"]]
 }
\ No newline at end of file
diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png
new file mode 100644
index 000000000..154039406
Binary files /dev/null and b/src/main/resources/assets/opencomputers/textures/blocks/hologram_effect.png differ
diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_side.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_side.png
new file mode 100644
index 000000000..99746701c
Binary files /dev/null and b/src/main/resources/assets/opencomputers/textures/blocks/hologram_side.png differ
diff --git a/src/main/resources/assets/opencomputers/textures/blocks/hologram_top.png b/src/main/resources/assets/opencomputers/textures/blocks/hologram_top.png
new file mode 100644
index 000000000..cebbf9d19
Binary files /dev/null and b/src/main/resources/assets/opencomputers/textures/blocks/hologram_top.png differ
diff --git a/src/main/resources/reference.conf b/src/main/resources/reference.conf
index 0977db7cd..47ebf3c32 100644
--- a/src/main/resources/reference.conf
+++ b/src/main/resources/reference.conf
@@ -456,6 +456,11 @@ opencomputers {
           # tick.
           screen: 0.05
 
+          # The amount of energy a hologram projetor consumes per tick. This
+          # is the cost if every column is lit. If not a single voxel is
+          # displayed the hologram projector will not drain energy.
+          hologram: 0.2
+
           # Energy it takes read one kilobyte from a file system. Note that non
           # I/O operations on file systems such as `list` or `getFreeSpace` do
           # *not* consume power. Note that this very much determines how much
diff --git a/src/main/scala/li/cil/oc/Blocks.scala b/src/main/scala/li/cil/oc/Blocks.scala
index 6a07c1970..d7dbb5a8f 100644
--- a/src/main/scala/li/cil/oc/Blocks.scala
+++ b/src/main/scala/li/cil/oc/Blocks.scala
@@ -21,6 +21,7 @@ object Blocks {
   var diskDrive: DiskDrive = _
   var keyboard: Keyboard = _
   var keyboardDeprecated: KeyboardDeprecated = _
+  var hologram: Hologram = _
   var powerConverter: PowerConverter = _
   var powerDistributor: PowerDistributor = _
   var redstone: Redstone = _
@@ -92,6 +93,7 @@ object Blocks {
     GameRegistry.registerTileEntity(classOf[tileentity.Charger], Settings.namespace + "charger")
     GameRegistry.registerTileEntity(classOf[tileentity.DiskDrive], Settings.namespace + "disk_drive")
     GameRegistry.registerTileEntity(classOf[tileentity.Keyboard], Settings.namespace + "keyboard")
+    GameRegistry.registerTileEntity(classOf[tileentity.Hologram], Settings.namespace + "hologram")
     GameRegistry.registerTileEntity(classOf[tileentity.PowerConverter], Settings.namespace + "power_converter")
     GameRegistry.registerTileEntity(classOf[tileentity.PowerDistributor], Settings.namespace + "power_distributor")
     GameRegistry.registerTileEntity(classOf[tileentity.Redstone], Settings.namespace + "redstone")
@@ -100,6 +102,9 @@ object Blocks {
     GameRegistry.registerTileEntity(classOf[tileentity.Screen], Settings.namespace + "screen")
     GameRegistry.registerTileEntity(classOf[tileentity.Rack], Settings.namespace + "serverRack")
 
+    // v1.2.2
+    hologram = Recipes.addBlockDelegate(new Hologram(blockSpecial), "hologram")
+
     register("oc:craftingCable", cable.createItemStack())
     register("oc:craftingCapacitor", capacitor.createItemStack())
     register("oc:craftingCaseTier1", case1.createItemStack())
diff --git a/src/main/scala/li/cil/oc/Items.scala b/src/main/scala/li/cil/oc/Items.scala
index 5b3582a8f..07a0784d4 100644
--- a/src/main/scala/li/cil/oc/Items.scala
+++ b/src/main/scala/li/cil/oc/Items.scala
@@ -94,9 +94,6 @@ object Items {
     upgradeGenerator = Recipes.addItemDelegate(new item.UpgradeGenerator(multi), "generatorUpgrade")
 
     ironNugget = new item.IronNugget(multi)
-    if (OreDictionary.getOres("nuggetIron").exists(ironNugget.createItemStack().isItemEqual)) {
-      Recipes.addItemDelegate(ironNugget, "nuggetIron")
-    }
 
     cuttingWire = Recipes.addItemDelegate(new item.CuttingWire(multi), "cuttingWire")
     acid = Recipes.addItemDelegate(new item.Acid(multi), "acid")
@@ -181,6 +178,10 @@ object Items {
     register("oc:craftingAcid", acid.createItemStack())
     register("oc:craftingGenerator", upgradeGenerator.createItemStack())
     register("oc:craftingSolarGenerator", upgradeSolarGenerator.createItemStack())
+
+    if (OreDictionary.getOres("nuggetIron").exists(ironNugget.createItemStack().isItemEqual)) {
+      Recipes.addItemDelegate(ironNugget, "nuggetIron")
+    }
   }
 
   def register(name: String, item: ItemStack) {
diff --git a/src/main/scala/li/cil/oc/Settings.scala b/src/main/scala/li/cil/oc/Settings.scala
index 9515877e1..07ca382b4 100644
--- a/src/main/scala/li/cil/oc/Settings.scala
+++ b/src/main/scala/li/cil/oc/Settings.scala
@@ -111,6 +111,7 @@ class Settings(config: Config) {
   val robotCost = config.getDouble("power.cost.robot") max 0
   val sleepCostFactor = config.getDouble("power.cost.sleepFactor") max 0
   val screenCost = config.getDouble("power.cost.screen") max 0
+  val hologramCost = config.getDouble("power.cost.hologram") max 0
   val hddReadCost = (config.getDouble("power.cost.hddRead") max 0) / 1024
   val hddWriteCost = (config.getDouble("power.cost.hddWrite") max 0) / 1024
   val gpuSetCost = (config.getDouble("power.cost.gpuSet") max 0) / Settings.basicScreenPixels
diff --git a/src/main/scala/li/cil/oc/client/PacketHandler.scala b/src/main/scala/li/cil/oc/client/PacketHandler.scala
index 505f9e989..a65b8484f 100644
--- a/src/main/scala/li/cil/oc/client/PacketHandler.scala
+++ b/src/main/scala/li/cil/oc/client/PacketHandler.scala
@@ -15,21 +15,26 @@ import net.minecraftforge.common.util.ForgeDirection
 import org.lwjgl.input.Keyboard
 
 object PacketHandler extends CommonPacketHandler {
+  @SubscribeEvent
+  def onPacket(e: ClientCustomPacketEvent) =
+    onPacketData(e.packet.payload, Minecraft.getMinecraft.thePlayer)
+
   protected override def world(player: EntityPlayer, dimension: Int) = {
     val world = player.worldObj
     if (world.provider.dimensionId == dimension) Some(world)
     else None
   }
 
-  @SubscribeEvent
-  def onPacket(e: ClientCustomPacketEvent) {
-    val p = new PacketParser(e.packet.payload, Minecraft.getMinecraft.thePlayer)
+  override def dispatch(p: PacketParser) {
     p.packetType match {
       case PacketType.AbstractBusState => onAbstractBusState(p)
       case PacketType.Analyze => onAnalyze(p)
       case PacketType.ChargerState => onChargerState(p)
       case PacketType.ComputerState => onComputerState(p)
       case PacketType.ComputerUserList => onComputerUserList(p)
+      case PacketType.HologramClear => onHologramClear(p)
+      case PacketType.HologramScale => onHologramScale(p)
+      case PacketType.HologramSet => onHologramSet(p)
       case PacketType.PowerState => onPowerState(p)
       case PacketType.RedstoneState => onRedstoneState(p)
       case PacketType.RobotAnimateSwing => onRobotAnimateSwing(p)
@@ -104,6 +109,38 @@ object PacketHandler extends CommonPacketHandler {
       case _ => // Invalid packet.
     }
 
+  def onHologramClear(p: PacketParser) =
+    p.readTileEntity[Hologram]() match {
+      case Some(t) =>
+        for (i <- 0 until t.volume.length) t.volume(i) = 0
+        t.dirty = true
+      case _ => // Invalid packet.
+    }
+
+  def onHologramScale(p: PacketParser) =
+    p.readTileEntity[Hologram]() match {
+      case Some(t) =>
+        t.scale = p.readDouble()
+        t.dirty = true
+      case _ => // Invalid packet.
+    }
+
+  def onHologramSet(p: PacketParser) =
+    p.readTileEntity[Hologram]() match {
+      case Some(t) =>
+        val fromX = p.readByte(): Int
+        val untilX = p.readByte(): Int
+        val fromZ = p.readByte(): Int
+        val untilZ = p.readByte(): Int
+        for (x <- fromX until untilX) {
+          for (z <- fromZ until untilZ) {
+            t.volume(x + z * t.width) = p.readInt()
+          }
+        }
+        t.dirty = true
+      case _ => // Invalid packet.
+    }
+
   def onPowerState(p: PacketParser) =
     p.readTileEntity[PowerInformation]() match {
       case Some(t) =>
diff --git a/src/main/scala/li/cil/oc/client/Proxy.scala b/src/main/scala/li/cil/oc/client/Proxy.scala
index caf240e1e..47df2d307 100644
--- a/src/main/scala/li/cil/oc/client/Proxy.scala
+++ b/src/main/scala/li/cil/oc/client/Proxy.scala
@@ -32,6 +32,7 @@ private[oc] class Proxy extends CommonProxy {
 
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Cable], CableRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Case], CaseRenderer)
+    ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Hologram], HologramRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.PowerDistributor], PowerDistributorRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.Rack], RackRenderer)
     ClientRegistry.bindTileEntitySpecialRenderer(classOf[tileentity.RobotProxy], RobotRenderer)
@@ -45,6 +46,7 @@ private[oc] class Proxy extends CommonProxy {
   override def postInit(e: FMLPostInitializationEvent) {
     super.postInit(e)
 
+    FMLCommonHandler.instance().bus().register(HologramRenderer)
     FMLCommonHandler.instance().bus().register(ScreenRenderer)
     if (Settings.get.rTreeDebugRenderer) {
       MinecraftForge.EVENT_BUS.register(WirelessNetworkDebugRenderer)
diff --git a/src/main/scala/li/cil/oc/client/Textures.scala b/src/main/scala/li/cil/oc/client/Textures.scala
index fe687c9bb..f088f4fc7 100644
--- a/src/main/scala/li/cil/oc/client/Textures.scala
+++ b/src/main/scala/li/cil/oc/client/Textures.scala
@@ -21,6 +21,7 @@ object Textures {
 
   val blockCable = new ResourceLocation(Settings.resourceDomain, "textures/blocks/cable.png")
   val blockCaseFrontOn = new ResourceLocation(Settings.resourceDomain, "textures/blocks/case_front_on.png")
+  val blockHologram = new ResourceLocation(Settings.resourceDomain, "textures/blocks/hologram_effect.png")
   val blockPowerDistributorOn = new ResourceLocation(Settings.resourceDomain, "textures/blocks/power_distributor_on.png")
   val blockRackFrontOn = new ResourceLocation(Settings.resourceDomain, "textures/blocks/rack_front_on.png")
   val blockRobot = new ResourceLocation(Settings.resourceDomain, "textures/blocks/robot.png")
diff --git a/src/main/scala/li/cil/oc/client/renderer/tileentity/CableRenderer.scala b/src/main/scala/li/cil/oc/client/renderer/tileentity/CableRenderer.scala
index b1359f776..9378c0cba 100644
--- a/src/main/scala/li/cil/oc/client/renderer/tileentity/CableRenderer.scala
+++ b/src/main/scala/li/cil/oc/client/renderer/tileentity/CableRenderer.scala
@@ -40,6 +40,7 @@ object CableRenderer extends TileEntitySpecialRenderer {
 
     for (mask <- 0 to 0xFF >> 2) {
       GL11.glNewList(displayLists + mask, GL11.GL_COMPILE)
+      t.startDrawingQuads()
       for (side <- ForgeDirection.VALID_DIRECTIONS) {
         val connects = (side.flag & mask) != 0
         val z = if (connects) 0 else lb
@@ -48,7 +49,6 @@ object CableRenderer extends TileEntitySpecialRenderer {
           exists(s => (s.flag & mask) != 0)) uo
         else 0
 
-        t.startDrawingQuads()
         t.setNormal(side.offsetX, side.offsetY, -side.offsetZ)
         val (tx, ty, tz, u, v) = side match {
           case ForgeDirection.WEST => (Array.fill(4)(z), t2, t1, uv1.reverse, uv2)
@@ -63,7 +63,6 @@ object CableRenderer extends TileEntitySpecialRenderer {
         t.addVertexWithUV(tx(1), ty(1), tz(1), u(1) + uc, v(1))
         t.addVertexWithUV(tx(2), ty(2), tz(2), u(2) + uc, v(2))
         t.addVertexWithUV(tx(3), ty(3), tz(3), u(3) + uc, v(3))
-        t.draw()
 
         if (connects) {
           val (axis, sign, uv1, uv2, uv3, uv4) = side match {
@@ -79,39 +78,32 @@ object CableRenderer extends TileEntitySpecialRenderer {
           val o1 = offsets((axis + sign + 3) % 3)
           val o2 = offsets((axis - sign + 3) % 3)
 
-          t.startDrawingQuads()
           normal(side, 0)
           t.addVertexWithUV(tx(0) - sign * tl(0), ty(0) - sign * tl(1), tz(0) - sign * tl(2), u(uv(0 + uv1)) + uo, v(uv(0 + uv1)) * vs)
           t.addVertexWithUV(tx(1) - sign * tl(0), ty(1) - sign * tl(1), tz(1) - sign * tl(2), u(uv(1 + uv1)) + uo, v(uv(1 + uv1)) * vs)
           t.addVertexWithUV(tx(2) + o1(0), ty(2) + o1(1), tz(2) + o1(2), u(uv(2 + uv1)) + uo, v(uv(2 + uv1)) * vs)
           t.addVertexWithUV(tx(3) + o1(0), ty(3) + o1(1), tz(3) + o1(2), u(uv(3 + uv1)) + uo, v(uv(3 + uv1)) * vs)
-          t.draw()
 
-          t.startDrawingQuads()
           normal(side, 1)
           t.addVertexWithUV(tx(0) - o1(0), ty(0) - o1(1), tz(0) - o1(2), u(uv(0 + uv2)) + uo, v(uv(0 + uv2)) * vs)
           t.addVertexWithUV(tx(1) - o1(0), ty(1) - o1(1), tz(1) - o1(2), u(uv(1 + uv2)) + uo, v(uv(1 + uv2)) * vs)
           t.addVertexWithUV(tx(2) - sign * tl(0), ty(2) - sign * tl(1), tz(2) - sign * tl(2), u(uv(2 + uv2)) + uo, v(uv(2 + uv2)) * vs)
           t.addVertexWithUV(tx(3) - sign * tl(0), ty(3) - sign * tl(1), tz(3) - sign * tl(2), u(uv(3 + uv2)) + uo, v(uv(3 + uv2)) * vs)
-          t.draw()
 
-          t.startDrawingQuads()
           normal(side, 2)
           t.addVertexWithUV(tx(0) - sign * tl(0), ty(0) - sign * tl(1), tz(0) - sign * tl(2), u(uv(0 + uv3)) + uo, v(uv(0 + uv3)) * vs)
           t.addVertexWithUV(tx(1) - o2(0), ty(1) - o2(1), tz(1) - o2(2), u(uv(1 + uv3)) + uo, v(uv(1 + uv3)) * vs)
           t.addVertexWithUV(tx(2) - o2(0), ty(2) - o2(1), tz(2) - o2(2), u(uv(2 + uv3)) + uo, v(uv(2 + uv3)) * vs)
           t.addVertexWithUV(tx(3) - sign * tl(0), ty(3) - sign * tl(1), tz(3) - sign * tl(2), u(uv(3 + uv3)) + uo, v(uv(3 + uv3)) * vs)
-          t.draw()
 
-          t.startDrawingQuads()
           normal(side, 3)
           t.addVertexWithUV(tx(0) + o2(0), ty(0) + o2(1), tz(0) + o2(2), u(uv(0 + uv4)) + uo, v(uv(0 + uv4)) * vs)
           t.addVertexWithUV(tx(1) - sign * tl(0), ty(1) - sign * tl(1), tz(1) - sign * tl(2), u(uv(1 + uv4)) + uo, v(uv(1 + uv4)) * vs)
           t.addVertexWithUV(tx(2) - sign * tl(0), ty(2) - sign * tl(1), tz(2) - sign * tl(2), u(uv(2 + uv4)) + uo, v(uv(2 + uv4)) * vs)
           t.addVertexWithUV(tx(3) + o2(0), ty(3) + o2(1), tz(3) + o2(2), u(uv(3 + uv4)) + uo, v(uv(3 + uv4)) * vs)
-          t.draw()
         }
       }
+      t.draw()
 
       GL11.glEndList()
     }
diff --git a/src/main/scala/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala b/src/main/scala/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
new file mode 100644
index 000000000..36ef696f6
--- /dev/null
+++ b/src/main/scala/li/cil/oc/client/renderer/tileentity/HologramRenderer.scala
@@ -0,0 +1,178 @@
+package li.cil.oc.client.renderer.tileentity
+
+import com.google.common.cache.{RemovalNotification, RemovalListener, CacheBuilder}
+import cpw.mods.fml.common.eventhandler.SubscribeEvent
+import cpw.mods.fml.common.gameevent.TickEvent.ClientTickEvent
+import java.util.concurrent.{Callable, TimeUnit}
+import li.cil.oc.common.tileentity.Hologram
+import li.cil.oc.util.RenderState
+import net.minecraft.client.renderer.tileentity.TileEntitySpecialRenderer
+import net.minecraft.client.renderer.{GLAllocation, Tessellator}
+import net.minecraft.tileentity.TileEntity
+import org.lwjgl.opengl.GL11
+import scala.util.Random
+import li.cil.oc.client.Textures
+
+object HologramRenderer extends TileEntitySpecialRenderer with Callable[Int] with RemovalListener[TileEntity, Int] {
+  val random = new Random()
+
+  /** We cache the display lists for the projectors we render for performance. */
+  val cache = com.google.common.cache.CacheBuilder.newBuilder().
+    expireAfterAccess(2, TimeUnit.SECONDS).
+    removalListener(this).
+    asInstanceOf[CacheBuilder[Hologram, Int]].
+    build[Hologram, Int]()
+
+  /** Used to pass the current screen along to call(). */
+  private var hologram: Hologram = null
+
+  override def renderTileEntityAt(te: TileEntity, x: Double, y: Double, z: Double, f: Float) {
+    hologram = te.asInstanceOf[Hologram]
+    if (!hologram.hasPower) return
+
+    GL11.glPushAttrib(0xFFFFFFFF)
+
+    GL11.glPushMatrix()
+    GL11.glTranslated(x + 0.5, y + 0.5, z + 0.5)
+    GL11.glScaled(1.001, 1.001, 1.001) // Avoid z-fighting with other blocks.
+    GL11.glTranslated(-1.5 * hologram.scale, 0, -1.5 * hologram.scale)
+
+    // Do a bit of flickering, because that's what holograms do!
+    if (random.nextDouble() < 0.025) {
+      GL11.glScaled(1 + random.nextGaussian() * 0.01, 1 + random.nextGaussian() * 0.001, 1 + random.nextGaussian() * 0.01)
+      GL11.glTranslated(random.nextGaussian() * 0.01, random.nextGaussian() * 0.01, random.nextGaussian() * 0.01)
+    }
+
+    // We do two passes here to avoid weird transparency effects: in the first
+    // pass we find the front-most fragment, in the second we actually draw it.
+    // TODO proper transparency shader? depth peeling e.g.
+    GL11.glColorMask(false, false, false, false)
+    val list = cache.get(hologram, this)
+    compileOrDraw(list)
+    GL11.glColorMask(true, true, true, true)
+    GL11.glDepthFunc(GL11.GL_EQUAL)
+    compileOrDraw(list)
+
+    GL11.glPopMatrix()
+    GL11.glPopAttrib()
+  }
+
+  def compileOrDraw(list: Int) = if (hologram.dirty) {
+    val doCompile = !RenderState.compilingDisplayList
+    if (doCompile) {
+      hologram.dirty = false
+      GL11.glNewList(list, GL11.GL_COMPILE_AND_EXECUTE)
+    }
+
+    def isSolid(hx: Int, hy: Int, hz: Int) = {
+      hx >= 0 && hy >= 0 && hz >= 0 && hx < hologram.width && hy < hologram.height && hz < hologram.width &&
+        (hologram.volume(hx + hz * hologram.width) & (1 << hy)) != 0
+    }
+
+    bindTexture(Textures.blockHologram)
+    val t = Tessellator.instance
+    t.startDrawingQuads()
+    t.setColorRGBA_F(1, 1, 1, 0.5f)
+
+    // TODO merge quads for better rendering performance
+    val s = 1f / 16f * hologram.scale
+    for (hx <- 0 until hologram.width) {
+      val wx = hx * s
+      for (hz <- 0 until hologram.width) {
+        val wz = hz * s
+        for (hy <- 0 until hologram.height) {
+          val wy = hy * s
+
+          if (isSolid(hx, hy, hz)) {
+            /*
+                  0---1
+                  | N |
+              0---3---2---1---0
+              | W | U | E | D |
+              5---6---7---4---5
+                  | S |
+                  5---4
+             */
+
+            // South
+            if (!isSolid(hx, hy, hz + 1)) {
+              t.setNormal(0, 0, 1)
+              t.addVertexWithUV(wx + s, wy + s, wz + s, 0, 0) // 5
+              t.addVertexWithUV(wx + 0, wy + s, wz + s, 1, 0) // 4
+              t.addVertexWithUV(wx + 0, wy + 0, wz + s, 1, 1) // 7
+              t.addVertexWithUV(wx + s, wy + 0, wz + s, 0, 1) // 6
+            }
+            // North
+            if (!isSolid(hx, hy, hz - 1)) {
+              t.setNormal(0, 0, -1)
+              t.addVertexWithUV(wx + s, wy + 0, wz + 0, 0, 0) // 3
+              t.addVertexWithUV(wx + 0, wy + 0, wz + 0, 1, 0) // 2
+              t.addVertexWithUV(wx + 0, wy + s, wz + 0, 1, 1) // 1
+              t.addVertexWithUV(wx + s, wy + s, wz + 0, 0, 1) // 0
+            }
+
+            // East
+            if (!isSolid(hx + 1, hy, hz)) {
+              t.setNormal(1, 0, 0)
+              t.addVertexWithUV(wx + s, wy + s, wz + s, 1, 0) // 5
+              t.addVertexWithUV(wx + s, wy + 0, wz + s, 1, 1) // 6
+              t.addVertexWithUV(wx + s, wy + 0, wz + 0, 0, 1) // 3
+              t.addVertexWithUV(wx + s, wy + s, wz + 0, 0, 0) // 0
+            }
+            // West
+            if (!isSolid(hx - 1, hy, hz)) {
+              t.setNormal(-1, 0, 0)
+              t.addVertexWithUV(wx + 0, wy + 0, wz + s, 1, 0) // 7
+              t.addVertexWithUV(wx + 0, wy + s, wz + s, 1, 1) // 4
+              t.addVertexWithUV(wx + 0, wy + s, wz + 0, 0, 1) // 1
+              t.addVertexWithUV(wx + 0, wy + 0, wz + 0, 0, 0) // 2
+            }
+
+            // Up
+            if (!isSolid(hx, hy + 1, hz)) {
+              t.setNormal(0, 1, 0)
+              t.addVertexWithUV(wx + s, wy + s, wz + 0, 0, 0) // 0
+              t.addVertexWithUV(wx + 0, wy + s, wz + 0, 1, 0) // 1
+              t.addVertexWithUV(wx + 0, wy + s, wz + s, 1, 1) // 4
+              t.addVertexWithUV(wx + s, wy + s, wz + s, 0, 1) // 5
+            }
+            // Down
+            if (!isSolid(hx, hy - 1, hz)) {
+              t.setNormal(0, -1, 0)
+              t.addVertexWithUV(wx + s, wy + 0, wz + s, 0, 0) // 6
+              t.addVertexWithUV(wx + 0, wy + 0, wz + s, 1, 0) // 7
+              t.addVertexWithUV(wx + 0, wy + 0, wz + 0, 1, 1) // 2
+              t.addVertexWithUV(wx + s, wy + 0, wz + 0, 0, 1) // 3
+            }
+          }
+        }
+      }
+    }
+
+    t.draw()
+
+    if (doCompile) {
+      GL11.glEndList()
+    }
+
+    true
+  }
+  else GL11.glCallList(list)
+
+  // ----------------------------------------------------------------------- //
+  // Cache
+  // ----------------------------------------------------------------------- //
+
+  def call = {
+    val list = GLAllocation.generateDisplayLists(1)
+    hologram.dirty = true // Force compilation.
+    list
+  }
+
+  def onRemoval(e: RemovalNotification[TileEntity, Int]) {
+    GLAllocation.deleteDisplayLists(e.getValue)
+  }
+
+  @SubscribeEvent
+  def onTick(e: ClientTickEvent) = cache.cleanUp()
+}
diff --git a/src/main/scala/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala b/src/main/scala/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
index 1b0170fa0..c7e014c87 100644
--- a/src/main/scala/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
+++ b/src/main/scala/li/cil/oc/client/renderer/tileentity/ScreenRenderer.scala
@@ -74,8 +74,7 @@ object ScreenRenderer extends TileEntitySpecialRenderer with Callable[Int] with
 
     if (screen.hasPower) {
       MonospaceFontRenderer.init(this.field_147501_a.field_147553_e)
-      val list = cache.get(screen, this)
-      compileOrDraw(list)
+      compileOrDraw(cache.get(screen, this))
     }
 
     GL11.glPopMatrix()
diff --git a/src/main/scala/li/cil/oc/common/PacketBuilder.scala b/src/main/scala/li/cil/oc/common/PacketBuilder.scala
index b0fe4dc26..80110be45 100644
--- a/src/main/scala/li/cil/oc/common/PacketBuilder.scala
+++ b/src/main/scala/li/cil/oc/common/PacketBuilder.scala
@@ -3,8 +3,8 @@ package li.cil.oc.common
 import cpw.mods.fml.common.FMLCommonHandler
 import cpw.mods.fml.common.network.internal.FMLProxyPacket
 import io.netty.buffer.Unpooled
-import java.io.ByteArrayOutputStream
-import java.io.DataOutputStream
+import java.io.{OutputStream, ByteArrayOutputStream, DataOutputStream}
+import java.util.zip.GZIPOutputStream
 import li.cil.oc.common.tileentity.TileEntity
 import li.cil.oc.OpenComputers
 import net.minecraft.entity.player.EntityPlayerMP
@@ -14,9 +14,8 @@ import net.minecraft.world.World
 import net.minecraftforge.common.util.ForgeDirection
 import scala.collection.convert.WrapAsScala._
 
-class PacketBuilder(packetType: PacketType.Value, private val stream: ByteArrayOutputStream = new ByteArrayOutputStream) extends DataOutputStream(stream) {
-  writeByte(packetType.id)
-
+// Necessary to keep track of the GZIP stream.
+abstract class PacketBuilderBase[T <: OutputStream](protected val stream: T) extends DataOutputStream(stream) {
   def writeTileEntity(t: TileEntity) = {
     writeInt(t.world.provider.dimensionId)
     writeInt(t.x)
@@ -57,5 +56,30 @@ class PacketBuilder(packetType: PacketType.Value, private val stream: ByteArrayO
 
   def sendToServer() = OpenComputers.channel.sendToServer(packet)
 
-  private def packet = new FMLProxyPacket(Unpooled.wrappedBuffer(stream.toByteArray), "OpenComputers")
+  protected def packet: FMLProxyPacket
 }
+
+class PacketBuilder(packetType: PacketType.Value) extends PacketBuilderBase(PacketBuilder.newData(compressed = false)) {
+  writeByte(packetType.id)
+
+  override protected def packet = {
+    new FMLProxyPacket(Unpooled.wrappedBuffer(stream.toByteArray), "OpenComputers")
+  }
+}
+
+class CompressedPacketBuilder(packetType: PacketType.Value, private val data: ByteArrayOutputStream = PacketBuilder.newData(compressed = true)) extends PacketBuilderBase(new GZIPOutputStream(data)) {
+  writeByte(packetType.id)
+
+  override protected def packet = {
+    stream.finish()
+    new FMLProxyPacket(Unpooled.wrappedBuffer(data.toByteArray), "OpenComputers")
+  }
+}
+
+object PacketBuilder {
+  def newData(compressed: Boolean) = {
+    val data = new ByteArrayOutputStream
+    data.write(if (compressed) 1 else 0)
+    data
+  }
+}
\ No newline at end of file
diff --git a/src/main/scala/li/cil/oc/common/PacketHandler.scala b/src/main/scala/li/cil/oc/common/PacketHandler.scala
index 04180ebf9..285bb0054 100644
--- a/src/main/scala/li/cil/oc/common/PacketHandler.scala
+++ b/src/main/scala/li/cil/oc/common/PacketHandler.scala
@@ -1,8 +1,10 @@
 package li.cil.oc.common
 
 import io.netty.buffer.{ByteBufInputStream, ByteBuf}
-import java.io.DataInputStream
-import li.cil.oc.Blocks
+import java.io.{InputStream, DataInputStream}
+import java.util.logging.Level
+import java.util.zip.GZIPInputStream
+import li.cil.oc.{Blocks, OpenComputers}
 import net.minecraft.entity.player.EntityPlayer
 import net.minecraft.item.ItemStack
 import net.minecraft.nbt.CompressedStreamTools
@@ -12,6 +14,21 @@ import scala.reflect.ClassTag
 import scala.reflect.classTag
 
 abstract class PacketHandler {
+  /** Top level dispatcher based on packet type. */
+  protected def onPacketData(data: ByteBuf, player: EntityPlayer) {
+    // Don't crash on badly formatted packets (may have been altered by a
+    // malicious client, in which case we don't want to allow it to kill the
+    // server like this). Just spam the log a bit... ;)
+    try {
+      val stream = new ByteBufInputStream(data)
+      if (stream.read() == 0) dispatch(new PacketParser(stream, player))
+      else dispatch(new PacketParser(new GZIPInputStream(stream), player))
+    } catch {
+      case e: Throwable =>
+        OpenComputers.log.log(Level.WARNING, "Received a badly formatted packet.", e)
+    }
+  }
+
   /**
    * Gets the world for the specified dimension.
    *
@@ -21,7 +38,9 @@ abstract class PacketHandler {
    */
   protected def world(player: EntityPlayer, dimension: Int): Option[World]
 
-  protected class PacketParser(data: ByteBuf, val player: EntityPlayer) extends DataInputStream(new ByteBufInputStream(data)) {
+  protected def dispatch(p: PacketParser)
+
+  protected class PacketParser(stream: InputStream, val player: EntityPlayer) extends DataInputStream(stream) {
     val packetType = PacketType(readByte())
 
     def getTileEntity[T: ClassTag](dimension: Int, x: Int, y: Int, z: Int): Option[T] = {
diff --git a/src/main/scala/li/cil/oc/common/PacketType.scala b/src/main/scala/li/cil/oc/common/PacketType.scala
index eb98c912c..74f1d21ce 100644
--- a/src/main/scala/li/cil/oc/common/PacketType.scala
+++ b/src/main/scala/li/cil/oc/common/PacketType.scala
@@ -8,6 +8,9 @@ object PacketType extends Enumeration {
   ChargerState,
   ComputerState,
   ComputerUserList,
+  HologramClear,
+  HologramScale,
+  HologramSet,
   PowerState,
   RedstoneState,
   RobotAnimateSwing,
diff --git a/src/main/scala/li/cil/oc/common/block/Delegate.scala b/src/main/scala/li/cil/oc/common/block/Delegate.scala
index 9eec7efe7..38bde161d 100644
--- a/src/main/scala/li/cil/oc/common/block/Delegate.scala
+++ b/src/main/scala/li/cil/oc/common/block/Delegate.scala
@@ -44,11 +44,11 @@ trait Delegate {
   // items in 1.7 when needed since IDs are no problem anymore.
   //  def canPlaceBlockOnSide(world: World, x: Int, y: Int, z: Int, side: ForgeDirection) = true
 
-  def bounds(world: World, x: Int, y: Int, z: Int) =
+  def bounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
     AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 1, 1)
 
   def updateBounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
-    parent.setBlockBounds(0, 0, 0, 1, 1, 1)
+    parent.setBlockBounds(bounds(world, x, y, z))
 
   def intersect(world: World, x: Int, y: Int, z: Int, origin: Vec3, direction: Vec3) =
     parent.superCollisionRayTrace(world, x, y, z, origin, direction)
diff --git a/src/main/scala/li/cil/oc/common/block/Hologram.scala b/src/main/scala/li/cil/oc/common/block/Hologram.scala
new file mode 100644
index 000000000..fe5c5093e
--- /dev/null
+++ b/src/main/scala/li/cil/oc/common/block/Hologram.scala
@@ -0,0 +1,53 @@
+package li.cil.oc.common.block
+
+import java.util
+import li.cil.oc.Settings
+import li.cil.oc.common.tileentity
+import li.cil.oc.util.Tooltip
+import net.minecraft.client.renderer.texture.IIconRegister
+import net.minecraft.entity.player.EntityPlayer
+import net.minecraft.item.{ItemStack, EnumRarity}
+import net.minecraft.world.{World, IBlockAccess}
+import net.minecraft.util.{IIcon, AxisAlignedBB}
+import net.minecraftforge.common.util.ForgeDirection
+
+class Hologram(val parent: SpecialDelegator) extends SpecialDelegate {
+  val unlocalizedName = "Hologram"
+
+  private val icons = Array.fill[IIcon](6)(null)
+
+  override def rarity = EnumRarity.rare
+
+  override def tooltipLines(stack: ItemStack, player: EntityPlayer, tooltip: util.List[String], advanced: Boolean) {
+    tooltip.addAll(Tooltip.get(unlocalizedName))
+  }
+
+  override def icon(side: ForgeDirection) = Some(icons(side.ordinal()))
+
+  override def luminance(world: IBlockAccess, x: Int, y: Int, z: Int) = 15
+
+  override def isSolid(world: IBlockAccess, x: Int, y: Int, z: Int, side: ForgeDirection) = side == ForgeDirection.DOWN
+
+  override def bounds(world: IBlockAccess, x: Int, y: Int, z: Int) =
+    AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 3 / 16f, 1)
+
+  override def itemBounds() {
+    parent.setBlockBounds(AxisAlignedBB.getAABBPool.getAABB(0, 0, 0, 1, 3 / 16f, 1))
+  }
+
+  override def registerIcons(iconRegister: IIconRegister) = {
+    icons(ForgeDirection.DOWN.ordinal) = iconRegister.registerIcon(Settings.resourceDomain + ":generic_top")
+    icons(ForgeDirection.UP.ordinal) = iconRegister.registerIcon(Settings.resourceDomain + ":hologram_top")
+
+    icons(ForgeDirection.NORTH.ordinal) = iconRegister.registerIcon(Settings.resourceDomain + ":hologram_side")
+    icons(ForgeDirection.SOUTH.ordinal) = icons(ForgeDirection.NORTH.ordinal)
+    icons(ForgeDirection.WEST.ordinal) = icons(ForgeDirection.NORTH.ordinal)
+    icons(ForgeDirection.EAST.ordinal) = icons(ForgeDirection.NORTH.ordinal)
+  }
+
+  // ----------------------------------------------------------------------- //
+
+  override def hasTileEntity = true
+
+  override def createTileEntity(world: World) = Some(new tileentity.Hologram())
+}
diff --git a/src/main/scala/li/cil/oc/common/tileentity/Hologram.scala b/src/main/scala/li/cil/oc/common/tileentity/Hologram.scala
new file mode 100644
index 000000000..e30a04afb
--- /dev/null
+++ b/src/main/scala/li/cil/oc/common/tileentity/Hologram.scala
@@ -0,0 +1,176 @@
+package li.cil.oc.common.tileentity
+
+import cpw.mods.fml.relauncher.{Side, SideOnly}
+import li.cil.oc.api.network._
+import li.cil.oc.server.{PacketSender => ServerPacketSender}
+import li.cil.oc.{Settings, api}
+import net.minecraft.nbt.NBTTagCompound
+import net.minecraft.util.AxisAlignedBB
+import net.minecraftforge.common.util.ForgeDirection
+
+class Hologram extends Environment with SidedEnvironment {
+  val node = api.Network.newNode(this, Visibility.Network).
+    withComponent("hologram").
+    withConnector().
+    create()
+
+  val width = 3 * 16
+
+  val height = 2 * 16 // 32 bit in an int
+
+  val volume = new Array[Int](width * width)
+
+  // Render scale.
+  var scale = 1.0
+
+  // Relative number of lit columns (for energy cost).
+  var litRatio = -1.0
+
+  // Whether we need to send an update packet/recompile our display list.
+  var dirty = false
+
+  // Interval of dirty columns.
+  var dirtyFromX = Int.MaxValue
+  var dirtyUntilX = -1
+  var dirtyFromZ = Int.MaxValue
+  var dirtyUntilZ = -1
+
+  // Time to wait before sending another update packet.
+  var cooldown = 5
+
+  var hasPower = true
+
+  def setDirty(x: Int, z: Int) {
+    dirty = true
+    dirtyFromX = math.min(dirtyFromX, x)
+    dirtyUntilX = math.max(dirtyUntilX, x + 1)
+    dirtyFromZ = math.min(dirtyFromZ, z)
+    dirtyUntilZ = math.max(dirtyUntilZ, z + 1)
+    litRatio = -1
+  }
+
+  def resetDirtyFlag() {
+    dirty = false
+    dirtyFromX = Int.MaxValue
+    dirtyUntilX = -1
+    dirtyFromZ = Int.MaxValue
+    dirtyUntilZ = -1
+    cooldown = 5
+  }
+
+  // ----------------------------------------------------------------------- //
+
+  override def canConnect(side: ForgeDirection) = side != ForgeDirection.UP
+
+  override def sidedNode(side: ForgeDirection) = node
+
+  // ----------------------------------------------------------------------- //
+
+  @Callback(doc = """function() -- Clears the hologram.""")
+  def clear(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
+    for (i <- 0 until volume.length) volume(i) = 0
+    ServerPacketSender.sendHologramClear(this)
+    resetDirtyFlag()
+    litRatio = 0
+    null
+  }
+
+  @Callback(direct = true, doc = """function(x:number, z:number):number -- Returns the bit mask representing the specified column.""")
+  def get(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
+    val x = args.checkInteger(0) - 1
+    val z = args.checkInteger(1) - 1
+    result(volume(x + z * width))
+  }
+
+  @Callback(direct = true, limit = 256, doc = """function(x:number, z:number, value:number) -- Set the bit mask for the specified column.""")
+  def set(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
+    val x = args.checkInteger(0) - 1
+    val z = args.checkInteger(1) - 1
+    val value = args.checkInteger(2)
+    volume(x + z * width) = value
+    setDirty(x, z)
+    null
+  }
+
+  @Callback(direct = true, limit = 128, doc = """function(x:number, z:number, height:number) -- Fills a column to the specified height.""")
+  def fill(computer: Context, args: Arguments): Array[AnyRef] = this.synchronized {
+    val x = args.checkInteger(0) - 1
+    val z = args.checkInteger(1) - 1
+    val height = math.min(32, math.max(0, args.checkInteger(2)))
+    // Bit shifts in the JVM only use the lowest five bits... so we have to
+    // manually check the height, to avoid the shift being a no-op.
+    volume(x + z * width) = if (height > 0) 0xFFFFFFFF >>> (32 - height) else 0
+    setDirty(x, z)
+    null
+  }
+
+  @Callback(doc = """function():number -- Returns the render scale of the hologram.""")
+  def getScale(computer: Context, args: Arguments): Array[AnyRef] = {
+    result(scale)
+  }
+
+  @Callback(doc = """function(value:number) -- Set the render scale. A larger scale consumes more energy.""")
+  def setScale(computer: Context, args: Arguments): Array[AnyRef] = {
+    scale = math.max(0.333333, math.min(3, args.checkDouble(0)))
+    ServerPacketSender.sendHologramScale(this)
+    null
+  }
+
+  // ----------------------------------------------------------------------- //
+
+  override def updateEntity() {
+    super.updateEntity()
+    if (isServer) {
+      if (dirty) {
+        cooldown -= 1
+        if (cooldown <= 0) {
+          ServerPacketSender.sendHologramSet(this)
+          resetDirtyFlag()
+        }
+      }
+      if (litRatio < 0) {
+        litRatio = 0
+        for (i <- 0 until volume.length) {
+          if (volume(i) != 0) litRatio += 1
+        }
+        litRatio /= volume.length
+      }
+
+      hasPower = node.changeBuffer(-Settings.get.hologramCost * litRatio * scale) == 0
+    }
+  }
+
+  // ----------------------------------------------------------------------- //
+
+  override def shouldRenderInPass(pass: Int) = pass == 1
+
+  override def getRenderBoundingBox = AxisAlignedBB.getAABBPool.getAABB(xCoord + 0.5 - 1.5 * scale, yCoord, zCoord - scale, xCoord + 0.5 + 1.5 * scale, yCoord + 0.25 + 2 * scale, zCoord + 0.5 + 1.5 * scale)
+
+  // ----------------------------------------------------------------------- //
+
+  override def readFromNBT(nbt: NBTTagCompound) {
+    super.readFromNBT(nbt)
+    nbt.getIntArray(Settings.namespace + "volume").copyToArray(volume)
+    scale = nbt.getDouble(Settings.namespace + "scale")
+  }
+
+  override def writeToNBT(nbt: NBTTagCompound) = this.synchronized {
+    super.writeToNBT(nbt)
+    nbt.setIntArray(Settings.namespace + "volume", volume)
+    nbt.setDouble(Settings.namespace + "scale", scale)
+  }
+
+  @SideOnly(Side.CLIENT)
+  override def readFromNBTForClient(nbt: NBTTagCompound) {
+    super.readFromNBTForClient(nbt)
+    nbt.getIntArray("volume").copyToArray(volume)
+    scale = nbt.getDouble("scale")
+    dirty = true
+  }
+
+  override def writeToNBTForClient(nbt: NBTTagCompound) {
+    super.writeToNBTForClient(nbt)
+    nbt.setIntArray("volume", volume)
+    nbt.setDouble("scale", scale)
+  }
+}
diff --git a/src/main/scala/li/cil/oc/server/PacketHandler.scala b/src/main/scala/li/cil/oc/server/PacketHandler.scala
index 0f0ee0437..8be3df353 100644
--- a/src/main/scala/li/cil/oc/server/PacketHandler.scala
+++ b/src/main/scala/li/cil/oc/server/PacketHandler.scala
@@ -14,12 +14,14 @@ import net.minecraftforge.common.DimensionManager
 import net.minecraftforge.common.util.ForgeDirection
 
 object PacketHandler extends CommonPacketHandler {
+  @SubscribeEvent
+  def onPacket(e: ServerCustomPacketEvent) =
+    onPacketData(e.packet.payload, e.handler.asInstanceOf[NetHandlerPlayServer].playerEntity)
+
   override protected def world(player: EntityPlayer, dimension: Int) =
     Option(DimensionManager.getWorld(dimension))
 
-  @SubscribeEvent
-  def onPacket(e: ServerCustomPacketEvent) {
-    val p = new PacketParser(e.packet.payload, e.handler.asInstanceOf[NetHandlerPlayServer].playerEntity)
+  override def dispatch(p: PacketParser) {
     p.packetType match {
       case PacketType.ComputerPower => onComputerPower(p)
       case PacketType.KeyDown => onKeyDown(p)
diff --git a/src/main/scala/li/cil/oc/server/PacketSender.scala b/src/main/scala/li/cil/oc/server/PacketSender.scala
index 8d19dfabe..1e909b0c8 100644
--- a/src/main/scala/li/cil/oc/server/PacketSender.scala
+++ b/src/main/scala/li/cil/oc/server/PacketSender.scala
@@ -1,9 +1,8 @@
 package li.cil.oc.server
 
 import li.cil.oc.common
-import li.cil.oc.common.PacketBuilder
-import li.cil.oc.common.PacketType
 import li.cil.oc.common.tileentity._
+import li.cil.oc.common.{CompressedPacketBuilder, PacketBuilder, PacketType}
 import li.cil.oc.util.PackedColor
 import net.minecraft.entity.player.EntityPlayerMP
 import net.minecraft.item.ItemStack
@@ -55,6 +54,40 @@ object PacketSender {
     pb.sendToNearbyPlayers(t)
   }
 
+  def sendHologramClear(t: Hologram) {
+    val pb = new PacketBuilder(PacketType.HologramClear)
+
+    pb.writeTileEntity(t)
+
+    pb.sendToNearbyPlayers(t)
+  }
+
+  def sendHologramScale(t: Hologram) {
+    val pb = new PacketBuilder(PacketType.HologramScale)
+
+    pb.writeTileEntity(t)
+    pb.writeDouble(t.scale)
+
+    pb.sendToNearbyPlayers(t)
+  }
+
+  def sendHologramSet(t: Hologram) {
+    val pb = new CompressedPacketBuilder(PacketType.HologramSet)
+
+    pb.writeTileEntity(t)
+    pb.writeByte(t.dirtyFromX)
+    pb.writeByte(t.dirtyUntilX)
+    pb.writeByte(t.dirtyFromZ)
+    pb.writeByte(t.dirtyUntilZ)
+    for (x <- t.dirtyFromX until t.dirtyUntilX) {
+      for (z <- t.dirtyFromZ until t.dirtyUntilZ) {
+        pb.writeInt(t.volume(x + z * t.width))
+      }
+    }
+
+    pb.sendToNearbyPlayers(t)
+  }
+
   def sendPowerState(t: PowerInformation) {
     val pb = new PacketBuilder(PacketType.PowerState)
 
diff --git a/src/main/scala/li/cil/oc/util/LuaStateFactory.scala b/src/main/scala/li/cil/oc/util/LuaStateFactory.scala
index 9f7179d76..19722d9cf 100644
--- a/src/main/scala/li/cil/oc/util/LuaStateFactory.scala
+++ b/src/main/scala/li/cil/oc/util/LuaStateFactory.scala
@@ -217,12 +217,12 @@ object LuaStateFactory {
           lua.getTop match {
             case 0 => lua.pushNumber(random.nextDouble())
             case 1 =>
-              val u = lua.checkInteger(1)
+              val u = lua.checkNumber(1).toInt
               lua.checkArg(1, 1 < u, "interval is empty")
               lua.pushInteger(1 + random.nextInt(u))
             case 2 =>
-              val l = lua.checkInteger(1)
-              val u = lua.checkInteger(2)
+              val l = lua.checkNumber(1).toInt
+              val u = lua.checkNumber(2).toInt
               lua.checkArg(1, l < u, "interval is empty")
               lua.pushInteger(l + random.nextInt(u - (l - 1)))
             case _ => throw new IllegalArgumentException("wrong number of arguments")