Also good to know:
Most Quest rewards and dungeon boss drops, as well as faction acquired, PvP rewards and some crafted items, are BoP - Bind on Pickup. That means that they bind to you when you take them, so that you will not be able to trade, sell or put that item on the AH. This one should avoid lots of lols at you.
Not all of the blues annd purples are bind on pickup, some of them are BoE - Bind on Equip, meaning that they will not be bound to you unless you equip them. Once you do equip them, they will be bound to you.