diff --git a/apps/openmw/CMakeLists.txt b/apps/openmw/CMakeLists.txt
index d7c229cf9..ca2355346 100644
--- a/apps/openmw/CMakeLists.txt
+++ b/apps/openmw/CMakeLists.txt
@@ -48,6 +48,7 @@ add_openmw_dir (mwworld
     refdata world physicssystem scene globals class action nullaction actionteleport
     containerstore actiontalk actiontake manualref player cellfunctors
     cells localscripts customdata weather inventorystore ptr actionread
+    timestamp
     )
 
 add_openmw_dir (mwclass
@@ -57,6 +58,7 @@ add_openmw_dir (mwclass
 
 add_openmw_dir (mwmechanics
     mechanicsmanager stat creaturestats magiceffects movement actors drawstate spells
+    activespells
     )
 
 add_openmw_dir (mwbase
diff --git a/apps/openmw/mwmechanics/activespells.cpp b/apps/openmw/mwmechanics/activespells.cpp
new file mode 100644
index 000000000..ced2a5c3f
--- /dev/null
+++ b/apps/openmw/mwmechanics/activespells.cpp
@@ -0,0 +1,162 @@
+
+#include "activespells.hpp"
+
+#include <cstdlib>
+
+#include "../mwbase/environment.hpp"
+
+#include "../mwworld/world.hpp"
+
+namespace MWMechanics
+{
+    void ActiveSpells::update() const
+    {
+        bool rebuild = false;
+
+        MWWorld::TimeStamp now = MWBase::Environment::get().getWorld()->getTimeStamp();
+
+        if (mLastUpdate!=now)
+        {
+            TContainer::iterator iter (mSpells.begin());
+            while (iter!=mSpells.end())
+                if (!timeToExpire (iter))
+                {
+                    mSpells.erase (iter++);
+                    rebuild = true;
+                }
+                else
+                    ++iter;
+
+            mLastUpdate = now;
+        }
+
+        if (mSpellsChanged)
+        {
+            mSpellsChanged = false;
+            rebuild = true;
+        }
+
+        if (rebuild)
+        {
+            mEffects = MagicEffects();
+
+            for (TIterator iter (begin()); iter!=end(); ++iter)
+            {
+                const ESM::Spell& spell =
+                    *MWBase::Environment::get().getWorld()->getStore().spells.find (iter->first);
+
+                const MWWorld::TimeStamp& start = iter->second.first;
+                float magnitude = iter->second.second;
+
+                for (std::vector<ESM::ENAMstruct>::const_iterator iter (spell.effects.list.begin());
+                    iter!=spell.effects.list.end(); ++iter)
+                {
+                    if (iter->duration)
+                    {
+                        MWWorld::TimeStamp end = start;
+                        end += static_cast<double> (iter->duration)*
+                            MWBase::Environment::get().getWorld()->getTimeScaleFactor()/(60*60);
+
+                        if (end>now)
+                        {
+                            EffectParam param;
+                            param.mMagnitude = static_cast<int> (
+                                (iter->magnMax-iter->magnMin+1)*magnitude + iter->magnMin);
+                            mEffects.add (*iter, param);
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    ActiveSpells::ActiveSpells()
+    : mSpellsChanged (false), mLastUpdate (MWBase::Environment::get().getWorld()->getTimeStamp())
+    {}
+
+    void ActiveSpells::addSpell (const std::string& id)
+    {
+        const ESM::Spell& spell = *MWBase::Environment::get().getWorld()->getStore().spells.find (id);
+
+        bool found = false;
+
+        for (std::vector<ESM::ENAMstruct>::const_iterator iter (spell.effects.list.begin());
+            iter!=spell.effects.list.end(); ++iter)
+        {
+            if (iter->duration)
+            {
+                found = true;
+                break;
+            }
+        }
+
+        if (!found)
+            return;
+
+        TContainer::iterator iter = mSpells.find (id);
+
+        float random = static_cast<float> (std::rand()) / RAND_MAX;
+
+        if (iter==mSpells.end())
+            mSpells.insert (std::make_pair (id,
+                std::make_pair (MWBase::Environment::get().getWorld()->getTimeStamp(), random)));
+        else
+            iter->second = std::make_pair (MWBase::Environment::get().getWorld()->getTimeStamp(), random);
+
+        mSpellsChanged = true;
+    }
+
+    void ActiveSpells::removeSpell (const std::string& id)
+    {
+        TContainer::iterator iter = mSpells.find (id);
+
+        if (iter!=mSpells.end())
+        {
+            mSpells.erase (iter);
+            mSpellsChanged = true;
+        }
+    }
+
+    const MagicEffects& ActiveSpells::getMagicEffects() const
+    {
+        update();
+        return mEffects;
+    }
+
+    ActiveSpells::TIterator ActiveSpells::begin() const
+    {
+        update();
+        return mSpells.begin();
+    }
+
+    ActiveSpells::TIterator ActiveSpells::end() const
+    {
+        update();
+        return mSpells.end();
+    }
+
+    double ActiveSpells::timeToExpire (const TIterator& iterator) const
+    {
+        const ESM::Spell& spell =
+            *MWBase::Environment::get().getWorld()->getStore().spells.find (iterator->first);
+
+        int duration = 0;
+
+        for (std::vector<ESM::ENAMstruct>::const_iterator iter (spell.effects.list.begin());
+            iter!=spell.effects.list.end(); ++iter)
+        {
+            if (iter->duration>duration)
+                duration = iter->duration;
+        }
+
+        double scaledDuration = duration *
+              MWBase::Environment::get().getWorld()->getTimeScaleFactor()/(60*60);
+
+        double usedUp = MWBase::Environment::get().getWorld()->getTimeStamp()-iterator->second.first;
+
+        if (usedUp>=scaledDuration)
+            return 0;
+
+        return scaledDuration-usedUp;
+    }
+}
diff --git a/apps/openmw/mwmechanics/activespells.hpp b/apps/openmw/mwmechanics/activespells.hpp
new file mode 100644
index 000000000..179321c58
--- /dev/null
+++ b/apps/openmw/mwmechanics/activespells.hpp
@@ -0,0 +1,58 @@
+#ifndef GAME_MWMECHANICS_ACTIVESPELLS_H
+#define GAME_MWMECHANICS_ACTIVESPELLS_H
+
+#include <map>
+#include <vector>
+#include <string>
+
+#include "../mwworld/timestamp.hpp"
+
+#include "magiceffects.hpp"
+
+namespace ESM
+{
+    struct Spell;
+}
+
+namespace MWMechanics
+{
+    /// \brief Lasting spell effects
+    class ActiveSpells
+    {
+        public:
+
+            typedef std::map<std::string, std::pair<MWWorld::TimeStamp, float> > TContainer;
+            typedef TContainer::const_iterator TIterator;
+
+        private:
+
+            mutable TContainer mSpells; // spellId, (time of casting, relative magnitude)
+            mutable MagicEffects mEffects;
+            mutable bool mSpellsChanged;
+            mutable MWWorld::TimeStamp mLastUpdate;
+
+            void update() const;
+
+        public:
+
+            ActiveSpells();
+
+            void addSpell (const std::string& id);
+            ///< Overwrites an existing spell with the same ID. If the spell does not have any
+            /// non-instant effects, it is ignored.
+
+            void removeSpell (const std::string& id);
+
+            const MagicEffects& getMagicEffects() const;
+
+            TIterator begin() const;
+
+            TIterator end() const;
+
+            double timeToExpire (const TIterator& iterator) const;
+            ///< Returns time (in in-game hours) until the spell pointed to by \a iterator
+            /// expires.
+    };
+}
+
+#endif
diff --git a/apps/openmw/mwmechanics/actors.cpp b/apps/openmw/mwmechanics/actors.cpp
index 849ab8ea4..5a17d50e4 100644
--- a/apps/openmw/mwmechanics/actors.cpp
+++ b/apps/openmw/mwmechanics/actors.cpp
@@ -8,11 +8,30 @@
 #include "../mwworld/class.hpp"
 #include "../mwworld/inventorystore.hpp"
 
+#include "creaturestats.hpp"
+
 namespace MWMechanics
 {
     void Actors::updateActor (const MWWorld::Ptr& ptr, float duration)
     {
+        // magic effects
+        adjustMagicEffects (ptr);
 
+        CreatureStats& creatureStats = MWWorld::Class::get (ptr).getCreatureStats (ptr);
+
+        // calculate dynamic stats
+        int strength = creatureStats.mAttributes[0].getBase();
+        int intelligence = creatureStats.mAttributes[1].getBase();
+        int willpower = creatureStats.mAttributes[2].getBase();
+        int agility = creatureStats.mAttributes[3].getBase();
+        int endurance = creatureStats.mAttributes[5].getBase();
+
+        double magickaFactor = creatureStats.mMagicEffects.get (EffectKey (84)).mMagnitude*0.1 + 0.5;
+
+        creatureStats.mDynamic[0].setBase (static_cast<int> (0.5 * (strength + endurance)));
+        creatureStats.mDynamic[1].setBase (static_cast<int> (intelligence +
+            magickaFactor * intelligence));
+        creatureStats.mDynamic[2].setBase (strength+willpower+agility+endurance);
     }
 
     void Actors::updateNpc (const MWWorld::Ptr& ptr, float duration, bool paused)
@@ -22,6 +41,27 @@ namespace MWMechanics
                 MWWorld::Class::get (ptr).getNpcStats (ptr));
     }
 
+    void Actors::adjustMagicEffects (const MWWorld::Ptr& creature)
+    {
+        CreatureStats& creatureStats =  MWWorld::Class::get (creature).getCreatureStats (creature);
+
+        MagicEffects now = creatureStats.mSpells.getMagicEffects();
+
+        if (creature.getTypeName()==typeid (ESM::NPC).name())
+        {
+            MWWorld::InventoryStore& store = MWWorld::Class::get (creature).getInventoryStore (creature);
+            now += store.getMagicEffects();
+        }
+
+        now += creatureStats.mActiveSpells.getMagicEffects();
+
+        MagicEffects diff = MagicEffects::diff (creatureStats.mMagicEffects, now);
+
+        creatureStats.mMagicEffects = now;
+
+        // TODO apply diff to other stats
+    }
+
     Actors::Actors() : mDuration (0) {}
 
     void Actors::addActor (const MWWorld::Ptr& ptr)
diff --git a/apps/openmw/mwmechanics/actors.hpp b/apps/openmw/mwmechanics/actors.hpp
index ae93fb52e..30e73ccf7 100644
--- a/apps/openmw/mwmechanics/actors.hpp
+++ b/apps/openmw/mwmechanics/actors.hpp
@@ -19,10 +19,10 @@ namespace MWMechanics
             std::set<MWWorld::Ptr> mActors;
             float mDuration;
 
-            void updateActor (const MWWorld::Ptr& ptr, float duration);
-
             void updateNpc (const MWWorld::Ptr& ptr, float duration, bool paused);
 
+            void adjustMagicEffects (const MWWorld::Ptr& creature);
+
         public:
 
             Actors();
@@ -39,6 +39,11 @@ namespace MWMechanics
             void update (std::vector<std::pair<std::string, Ogre::Vector3> >& movement,
                 float duration, bool paused);
             ///< Update actor stats and store desired velocity vectors in \a movement
+
+            void updateActor (const MWWorld::Ptr& ptr, float duration);
+            ///< This function is normally called automatically during the update process, but it can
+            /// also be called explicitly at any time to force an update.
+
     };
 }
 
diff --git a/apps/openmw/mwmechanics/creaturestats.hpp b/apps/openmw/mwmechanics/creaturestats.hpp
index ab008da9e..cc3c409da 100644
--- a/apps/openmw/mwmechanics/creaturestats.hpp
+++ b/apps/openmw/mwmechanics/creaturestats.hpp
@@ -7,6 +7,7 @@
 #include "stat.hpp"
 #include "magiceffects.hpp"
 #include "spells.hpp"
+#include "activespells.hpp"
 
 namespace MWMechanics
 {
@@ -16,6 +17,7 @@ namespace MWMechanics
         DynamicStat<int> mDynamic[3]; // health, magicka, fatigue
         int mLevel;
         Spells mSpells;
+        ActiveSpells mActiveSpells;
         MagicEffects mMagicEffects;
     };
 }
diff --git a/apps/openmw/mwmechanics/magiceffects.cpp b/apps/openmw/mwmechanics/magiceffects.cpp
index 1c73bf1b1..a77e19966 100644
--- a/apps/openmw/mwmechanics/magiceffects.cpp
+++ b/apps/openmw/mwmechanics/magiceffects.cpp
@@ -1,6 +1,8 @@
 
 #include "magiceffects.hpp"
 
+#include <cstdlib>
+
 #include <stdexcept>
 
 #include <components/esm/defs.hpp>
@@ -66,6 +68,46 @@ namespace MWMechanics
         }
     }
 
+    void MagicEffects::add (const ESM::EffectList& list)
+    {
+        for (std::vector<ESM::ENAMstruct>::const_iterator iter (list.list.begin()); iter!=list.list.end();
+            ++iter)
+        {
+            EffectParam param;
+
+            if (iter->magnMin>=iter->magnMax)
+                param.mMagnitude = iter->magnMin;
+            else
+                param.mMagnitude = static_cast<int> (
+                    (iter->magnMax-iter->magnMin+1)*
+                    (static_cast<float> (std::rand()) / RAND_MAX) + iter->magnMin);
+
+            add (*iter, param);
+        }
+    }
+
+    MagicEffects& MagicEffects::operator+= (const MagicEffects& effects)
+    {
+        if (this==&effects)
+        {
+            MagicEffects temp (effects);
+            *this += temp;
+            return *this;
+        }
+
+        for (Collection::const_iterator iter (effects.begin()); iter!=effects.end(); ++iter)
+        {
+            Collection::iterator result = mCollection.find (iter->first);
+
+            if (result!=mCollection.end())
+                result->second += iter->second;
+            else
+                mCollection.insert (*iter);
+        }
+
+        return *this;
+    }
+
     EffectParam MagicEffects::get (const EffectKey& key) const
     {
         Collection::const_iterator iter = mCollection.find (key);
@@ -85,11 +127,11 @@ namespace MWMechanics
         MagicEffects result;
 
         // adding/changing
-        for (Collection::const_iterator iter (now.Begin()); iter!=now.End(); ++iter)
+        for (Collection::const_iterator iter (now.begin()); iter!=now.end(); ++iter)
         {
             Collection::const_iterator other = prev.mCollection.find (iter->first);
 
-            if (other==prev.End())
+            if (other==prev.end())
             {
                 // adding
                 result.add (iter->first, iter->second);
@@ -102,17 +144,16 @@ namespace MWMechanics
         }
 
         // removing
-        for (Collection::const_iterator iter (prev.Begin()); iter!=prev.End(); ++iter)
+        for (Collection::const_iterator iter (prev.begin()); iter!=prev.end(); ++iter)
         {
             Collection::const_iterator other = now.mCollection.find (iter->first);
 
-            if (other==prev.End())
+            if (other==prev.end())
             {
                 result.add (iter->first, EffectParam() - iter->second);
             }
         }
 
         return result;
-
     }
 }
diff --git a/apps/openmw/mwmechanics/magiceffects.hpp b/apps/openmw/mwmechanics/magiceffects.hpp
index 3d36ea813..2f61d7eeb 100644
--- a/apps/openmw/mwmechanics/magiceffects.hpp
+++ b/apps/openmw/mwmechanics/magiceffects.hpp
@@ -6,6 +6,7 @@
 namespace ESM
 {
     struct ENAMstruct;
+    struct EffectList;
 }
 
 namespace MWMechanics
@@ -60,12 +61,16 @@ namespace MWMechanics
 
         public:
 
-            Collection::const_iterator Begin() const { return mCollection.begin(); }
+            Collection::const_iterator begin() const { return mCollection.begin(); }
 
-            Collection::const_iterator End() const { return mCollection.end(); }
+            Collection::const_iterator end() const { return mCollection.end(); }
 
             void add (const EffectKey& key, const EffectParam& param);
 
+            void add (const ESM::EffectList& list);
+
+            MagicEffects& operator+= (const MagicEffects& effects);
+
             EffectParam get (const EffectKey& key) const;
             ///< This function can safely be used for keys that are not present.
 
diff --git a/apps/openmw/mwmechanics/mechanicsmanager.cpp b/apps/openmw/mwmechanics/mechanicsmanager.cpp
index 8bc408be6..0c48d8894 100644
--- a/apps/openmw/mwmechanics/mechanicsmanager.cpp
+++ b/apps/openmw/mwmechanics/mechanicsmanager.cpp
@@ -139,42 +139,13 @@ namespace MWMechanics
             }
         }
 
-        // magic effects
-        adjustMagicEffects (ptr);
-
-        // calculate dynamic stats
-        int strength = creatureStats.mAttributes[0].getBase();
-        int intelligence = creatureStats.mAttributes[1].getBase();
-        int willpower = creatureStats.mAttributes[2].getBase();
-        int agility = creatureStats.mAttributes[3].getBase();
-        int endurance = creatureStats.mAttributes[5].getBase();
-
-        double magickaFactor = creatureStats.mMagicEffects.get (EffectKey (84)).mMagnitude*0.1 + 0.5;
-
-        creatureStats.mDynamic[0].setBase (static_cast<int> (0.5 * (strength + endurance)));
-        creatureStats.mDynamic[1].setBase (static_cast<int> (intelligence +
-            magickaFactor * intelligence));
-        creatureStats.mDynamic[2].setBase (strength+willpower+agility+endurance);
+        // forced update and current value adjustments
+        mActors.updateActor (ptr, 0);
 
         for (int i=0; i<3; ++i)
             creatureStats.mDynamic[i].setCurrent (creatureStats.mDynamic[i].getModified());
     }
 
-    void MechanicsManager::adjustMagicEffects (MWWorld::Ptr& creature)
-    {
-        MWMechanics::CreatureStats& creatureStats =
-            MWWorld::Class::get (creature).getCreatureStats (creature);
-
-        MagicEffects now = creatureStats.mSpells.getMagicEffects();
-
-        /// \todo add effects from active spells and equipment
-
-        MagicEffects diff = MagicEffects::diff (creatureStats.mMagicEffects, now);
-
-        creatureStats.mMagicEffects = now;
-
-        // TODO apply diff to other stats
-    }
 
     MechanicsManager::MechanicsManager()
     : mUpdatePlayer (true), mClassSelected (false),
diff --git a/apps/openmw/mwmechanics/mechanicsmanager.hpp b/apps/openmw/mwmechanics/mechanicsmanager.hpp
index a26fb98cd..62bb4cf7e 100644
--- a/apps/openmw/mwmechanics/mechanicsmanager.hpp
+++ b/apps/openmw/mwmechanics/mechanicsmanager.hpp
@@ -31,8 +31,6 @@ namespace MWMechanics
             ///< build player according to stored class/race/birthsign information. Will
             /// default to the values of the ESM::NPC object, if no explicit information is given.
 
-            void adjustMagicEffects (MWWorld::Ptr& creature);
-
         public:
 
             MechanicsManager ();
diff --git a/apps/openmw/mwmechanics/spells.cpp b/apps/openmw/mwmechanics/spells.cpp
index a53c75dc2..af43cdfb5 100644
--- a/apps/openmw/mwmechanics/spells.cpp
+++ b/apps/openmw/mwmechanics/spells.cpp
@@ -13,13 +13,7 @@ namespace MWMechanics
 {
     void Spells::addSpell (const ESM::Spell *spell, MagicEffects& effects) const
     {
-        for (std::vector<ESM::ENAMstruct>::const_iterator iter = spell->effects.list.begin();
-            iter!=spell->effects.list.end(); ++iter)
-        {
-            EffectParam param;
-            param.mMagnitude = iter->magnMax; /// \todo calculate magnitude
-            effects.add (EffectKey (*iter), param);
-        }
+        effects.add (spell->effects);
     }
 
     Spells::TIterator Spells::begin() const
diff --git a/apps/openmw/mwworld/containerstore.hpp b/apps/openmw/mwworld/containerstore.hpp
index 3cb3f3bdc..f677e0dcb 100644
--- a/apps/openmw/mwworld/containerstore.hpp
+++ b/apps/openmw/mwworld/containerstore.hpp
@@ -90,7 +90,7 @@ namespace MWWorld
             void clear();
             ///< Empty container.
 
-            void flagAsModified();
+            virtual void flagAsModified();
             ///< \attention This function is internal to the world model and should not be called from
             /// outside.
 
diff --git a/apps/openmw/mwworld/inventorystore.cpp b/apps/openmw/mwworld/inventorystore.cpp
index 3e535793c..98ab1665b 100644
--- a/apps/openmw/mwworld/inventorystore.cpp
+++ b/apps/openmw/mwworld/inventorystore.cpp
@@ -4,6 +4,12 @@
 #include <iterator>
 #include <algorithm>
 
+#include <components/esm/loadench.hpp>
+
+#include "../mwbase/environment.hpp"
+
+#include "../mwworld/world.hpp"
+
 #include "../mwmechanics/npcstats.hpp"
 
 #include "class.hpp"
@@ -32,7 +38,7 @@ void MWWorld::InventoryStore::initSlots (TSlots& slots)
         slots.push_back (end());
 }
 
-MWWorld::InventoryStore::InventoryStore()
+MWWorld::InventoryStore::InventoryStore() : mMagicEffectsUpToDate (false)
 {
     initSlots (mSlots);
 }
@@ -40,11 +46,15 @@ MWWorld::InventoryStore::InventoryStore()
 MWWorld::InventoryStore::InventoryStore (const InventoryStore& store)
 : ContainerStore (store)
 {
+    mMagicEffects = store.mMagicEffects;
+    mMagicEffectsUpToDate = store.mMagicEffectsUpToDate;
     copySlots (store);
 }
 
 MWWorld::InventoryStore& MWWorld::InventoryStore::operator= (const InventoryStore& store)
 {
+    mMagicEffects = store.mMagicEffects;
+    mMagicEffectsUpToDate = store.mMagicEffectsUpToDate;
     ContainerStore::operator= (store);
     mSlots.clear();
     copySlots (store);
@@ -201,6 +211,39 @@ void MWWorld::InventoryStore::autoEquip (const MWMechanics::NpcStats& stats)
     }
 }
 
+const MWMechanics::MagicEffects& MWWorld::InventoryStore::getMagicEffects()
+{
+    if (!mMagicEffectsUpToDate)
+    {
+        mMagicEffects = MWMechanics::MagicEffects();
+
+        for (TSlots::const_iterator iter (mSlots.begin()); iter!=mSlots.end(); ++iter)
+            if (*iter!=end())
+            {
+                std::string enchantmentId = MWWorld::Class::get (**iter).getEnchantment (**iter);
+
+                if (!enchantmentId.empty())
+                {
+                    const ESM::Enchantment& enchantment =
+                        *MWBase::Environment::get().getWorld()->getStore().enchants.find (enchantmentId);
+
+                    if (enchantment.data.type==ESM::Enchantment::ConstantEffect)
+                        mMagicEffects.add (enchantment.effects);
+                }
+            }
+
+        mMagicEffectsUpToDate = true;
+    }
+
+    return mMagicEffects;
+}
+
+void MWWorld::InventoryStore::flagAsModified()
+{
+    ContainerStore::flagAsModified();
+    mMagicEffectsUpToDate = false;
+}
+
 bool MWWorld::InventoryStore::stacks(const Ptr& ptr1, const Ptr& ptr2)
 {
     bool canStack = MWWorld::ContainerStore::stacks(ptr1, ptr2);
diff --git a/apps/openmw/mwworld/inventorystore.hpp b/apps/openmw/mwworld/inventorystore.hpp
index 05fc651ee..dcfb21f30 100644
--- a/apps/openmw/mwworld/inventorystore.hpp
+++ b/apps/openmw/mwworld/inventorystore.hpp
@@ -3,6 +3,8 @@
 
 #include "containerstore.hpp"
 
+#include "../mwmechanics/magiceffects.hpp"
+
 namespace MWMechanics
 {
     struct NpcStats;
@@ -41,6 +43,9 @@ namespace MWWorld
 
         private:
 
+            mutable MWMechanics::MagicEffects mMagicEffects;
+            mutable bool mMagicEffectsUpToDate;
+
             typedef std::vector<ContainerStoreIterator> TSlots;
 
             mutable TSlots mSlots;
@@ -65,6 +70,15 @@ namespace MWWorld
             void autoEquip (const MWMechanics::NpcStats& stats);
             ///< Auto equip items according to stats and item value.
 
+            const MWMechanics::MagicEffects& getMagicEffects();
+            ///< Return magic effects from worn items.
+            ///
+            /// \todo make this const again, after the constness of Ptrs and iterators has been addressed.
+
+            virtual void flagAsModified();
+            ///< \attention This function is internal to the world model and should not be called from
+            /// outside.
+
         protected:
 
             virtual bool stacks (const Ptr& ptr1, const Ptr& ptr2);
diff --git a/apps/openmw/mwworld/timestamp.cpp b/apps/openmw/mwworld/timestamp.cpp
new file mode 100644
index 000000000..e2f3d6c63
--- /dev/null
+++ b/apps/openmw/mwworld/timestamp.cpp
@@ -0,0 +1,108 @@
+
+#include "timestamp.hpp"
+
+#include <cmath>
+
+#include <stdexcept>
+
+namespace MWWorld
+{
+    TimeStamp::TimeStamp (float hour, int day)
+    : mHour (hour), mDay (day)
+    {
+        if (hour<0 || hour>=24 || day<0)
+            throw std::runtime_error ("invalid time stamp");
+    }
+
+    float TimeStamp::getHour() const
+    {
+        return mHour;
+    }
+
+    int TimeStamp::getDay() const
+    {
+        return mDay;
+    }
+
+    TimeStamp& TimeStamp::operator+= (double hours)
+    {
+        if (hours<0)
+            throw std::runtime_error ("can't move time stamp backwards in time");
+
+        hours += mHour;
+
+        mHour = static_cast<float> (std::fmod (hours, 24));
+
+        mDay += hours / 24;
+
+        return *this;
+    }
+
+    bool operator== (const TimeStamp& left, const TimeStamp& right)
+    {
+        return left.getHour()==right.getHour() && left.getDay()==right.getDay();
+    }
+
+    bool operator!= (const TimeStamp& left, const TimeStamp& right)
+    {
+        return !(left==right);
+    }
+
+    bool operator< (const TimeStamp& left, const TimeStamp& right)
+    {
+        if (left.getDay()<right.getDay())
+            return true;
+
+        if (left.getDay()>right.getDay())
+            return false;
+
+        return left.getHour()<right.getHour();
+    }
+
+    bool operator<= (const TimeStamp& left, const TimeStamp& right)
+    {
+        return left<right || left==right;
+    }
+
+    bool operator> (const TimeStamp& left, const TimeStamp& right)
+    {
+        return !(left<=right);
+    }
+
+    bool operator>= (const TimeStamp& left, const TimeStamp& right)
+    {
+        return !(left<right);
+    }
+
+    TimeStamp operator+ (const TimeStamp& stamp, double hours)
+    {
+        return TimeStamp (stamp) + hours;
+    }
+
+    TimeStamp operator+ (double hours, const TimeStamp& stamp)
+    {
+        return TimeStamp (stamp) + hours;
+    }
+
+    double operator- (const TimeStamp& left, const TimeStamp& right)
+    {
+        if (left<right)
+            return -(right-left);
+
+        int days = left.getDay() - right.getDay();
+
+        double hours = 0;
+
+        if (left.getHour()<right.getHour())
+        {
+            hours = 24-right.getHour()+left.getHour();
+            ++days;
+        }
+        else
+        {
+            hours = left.getHour()-right.getHour();
+        }
+
+        return hours + 24*days;
+    }
+}
diff --git a/apps/openmw/mwworld/timestamp.hpp b/apps/openmw/mwworld/timestamp.hpp
new file mode 100644
index 000000000..e2d8b242a
--- /dev/null
+++ b/apps/openmw/mwworld/timestamp.hpp
@@ -0,0 +1,44 @@
+#ifndef GAME_MWWORLD_TIMESTAMP_H
+#define GAME_MWWORLD_TIMESTAMP_H
+
+namespace MWWorld
+{
+    /// \brief In-game time stamp
+    ///
+    /// This class is based on the global variables GameHour and DaysPassed.
+    class TimeStamp
+    {
+            float mHour;
+            int mDay;
+
+        public:
+
+            explicit TimeStamp (float hour = 0, int day = 0);
+            ///< \oaram hour [0, 23)
+            /// \param day >=0
+
+            float getHour() const;
+
+            int getDay() const;
+
+            TimeStamp& operator+= (double hours);
+            ///< \param hours >=0
+    };
+
+    bool operator== (const TimeStamp& left, const TimeStamp& right);
+    bool operator!= (const TimeStamp& left, const TimeStamp& right);
+
+    bool operator< (const TimeStamp& left, const TimeStamp& right);
+    bool operator<= (const TimeStamp& left, const TimeStamp& right);
+
+    bool operator> (const TimeStamp& left, const TimeStamp& right);
+    bool operator>= (const TimeStamp& left, const TimeStamp& right);
+
+    TimeStamp operator+ (const TimeStamp& stamp, double hours);
+    TimeStamp operator+ (double hours, const TimeStamp& stamp);
+
+    double operator- (const TimeStamp& left, const TimeStamp& right);
+    ///< Returns the difference between \a left and \a right in in-game hours.
+}
+
+#endif
diff --git a/apps/openmw/mwworld/world.cpp b/apps/openmw/mwworld/world.cpp
index 4adaf7918..eeda92277 100644
--- a/apps/openmw/mwworld/world.cpp
+++ b/apps/openmw/mwworld/world.cpp
@@ -471,6 +471,12 @@ namespace MWWorld
         mRendering->skySetDate (mGlobalVariables->getInt ("day"), month);
     }
 
+    TimeStamp World::getTimeStamp() const
+    {
+        return TimeStamp (mGlobalVariables->getFloat ("gamehour"),
+            mGlobalVariables->getInt ("dayspassed"));
+    }
+
     bool World::toggleSky()
     {
         if (mSky)
diff --git a/apps/openmw/mwworld/world.hpp b/apps/openmw/mwworld/world.hpp
index 7359f8b90..49a3cf029 100644
--- a/apps/openmw/mwworld/world.hpp
+++ b/apps/openmw/mwworld/world.hpp
@@ -18,6 +18,7 @@
 #include "physicssystem.hpp"
 #include "cells.hpp"
 #include "localscripts.hpp"
+#include "timestamp.hpp"
 
 #include <openengine/bullet/physic.hpp>
 #include <openengine/ogre/fader.hpp>
@@ -185,6 +186,9 @@ namespace MWWorld
             void setDay (int day);
             ///< Set in-game time day.
 
+            TimeStamp getTimeStamp() const;
+            ///< Return current in-game time stamp.
+
             bool toggleSky();
             ///< \return Resulting mode