DM_Matt - Allright, How's this sound:
Wardrobe Robe
The wearer of this ordinary looking robe can command it to become any nonmagical type of clothing, the change takes one full round and lasts for 12 hours before the robe reverts to its ordinary form, or until the wearer wills it to become something else. If the robe (Or whatever form of clothing it's in) is ripped or if any part is removed a distance of more than 5 feet from it, the magic is destroyed and it becomes permanently a non-magical, ordinary robe.
The robe radiates light transmutation magic at all times.
Cost: 3,000 GP
Then never mind, I'll just stick with the hat. thats WAY too easy to break. I really don't understand why you find the item so powerful.