I crocheted this coffee cup cozy from wool yarn and washed and dried it to felt it. Now it works great as a replacement for those cardboard ones that you get at the coffee shop. I need to make a couple more to work out the pattern. This is actually not my first attempt at this. I made one about a year ago that was much too large, thinking it would shrink a lot when I washed it, but it didn't. Then I started making a second one, but made too many increases too early so it was okay at the bottom, but huge at the top. This one is about the right size, so I'll have to see if I can replicate it!