aEqItemLvl is a simple addon that adds average equipped item level to the game tooltip. It works on any target that is not an npc.
Update: addon does not include gear upgrades. -- fixed
Update: addon does not calculate heirloom items.
Update: addon does not calculate all items in inspected inventory due to inspect lag. -- need to mouseover 2nd time with shift modifier pressed
Update: gear calcualte function is abit incorrect. -- fixed