Metal, sort of. It's thinner, and it's far more malleable. They make cute boat hats, if you press them the right way.

I've seen people with a sort of a bird with metal plating on it -- it doesn't look practical in the air, but I think that it still flies. Barring that, a pidgeot is always a classic choice. [Pause. Consideration.] ... someone should make a list of all these types of birds, actually. I'm having a little trouble keeping track of all of them.