I had several old leather belts that had been lying around in the goodwill pile for literally months! I thought they were really cool though and so I saved them. I'm happy I did, because I was able to 'recycle' them!
This one is a stirrup keeper:
This next one is a handle thing on the front of my english saddle. :) I can use it to attach the end of my mecate lead rope to.
Slobber straps. The one on the left is from a pair I bought. The two on the right are the ones I made. Saved myself $15!
With the scraps I made bracelets.
If someone were really ambitious and wanted to take the time to stitch and add buckles etc., you could probably make a bridle or halter and maybe even hobbles...
That's it... Feel free to comment and post any other Ideas you have!!