well i've done a couple different things.
1. glue a few small strips of leather together to form a thick shelf.
2. used a small piece of wood sanded down.
3. tooth of an animal looks good and works good. (looks really cool when it's from a big predator, like bear or cougar!)
4. smooth polished stone. (have to rough up a flat side to get glue to work, but it looks unusual.)
sorry no pictures. but there's some idea's for you.