When I first came back to crochet a couple of years ago, my first project was to crochet a bag that I would felt. Big mistake. On a road trip to Canberra I grabbed some yarn and got busy. What I hadn't checked was that the yarn was actually a treated wool that would not felt. So after many attempts to felt, I gave up in discussed and left it in the cupboard.
Fast forward about 18 months, and I pulled out the failed bag with the hope of doing something with it. I spotted a cheap ottoman in Spotlight and the idea formed to use the "bag" to cover the ottoman. I think it has worked well. So glad I didn't just throw it out.