I have a bag of saddle scraps so I just used that, but I think I'd try it with suede next time. the piece I had that was big enough had a cheap looking finish, so I sanded it off and used some old walnuts I had to oil it and make it soft and dark. a good way to get the most oil out of the nut was to squeeze them through my garlic press to make a paste.
it holds quite a bit of change but it's still pretty small. I like how it came out, but I think my favorite part of it is the smell!