Do you have chairs that aren't fit for sitting on anymore? Why not remove the legs and cut the seat down and make it a shelf. The picture below is one used for outdoor decoration and I sprayed it with crackle paint, then I embellished with recycled junk. And indoor chair has many possibilities too!
I hung my chair by drilling straight through with a big wood screw. Shh...don't tell my hubby it's straight through the siding too. You could hang yours with a picture bracket, but beware in high wind if you hang it outside. It could blow off the wall during the night and wake you from a deep sleep thinking you had an intruder. You can see the ramifications of that problem...
Note: The seat was removed and replaced with a board, so only the top of the original chair was used. But you could use the chair seat and saw it off to be a little shorter in depth.
I'm linking this post up to Mustard See Creations for Furniture Feature Friday. Check out Miss Mustard Seed's blog for some great ideas!