Felted Crochet

On this topic, I am the messager rather than the expert. I have done a little bit of accidental felting by putting a couple of afghans in the washing machine. They come out a little bit fuzzier every time I wash them.
Here are the basics as I understand them. It's useful to make a small sample from the same yarn that you are planning to use for the project. The yarn should not say "Machine Washable" and it should be at least 50% animal hair. Wool, llama, alpaca, and mohair are good choices. Sometimes the colors will fade or blend at the edges of stripes.
To felt by hand, you soak the piece in warm, soapy (use pure soap like Ivory) water and rub the yarn against itself, changing directions as you go so that every part gets rubbed. When you think it's fuzzy enough, dip the piece in cold water and rub a little more to make sure it's the way you want it to look. If it isn't finished, put it back in the warm water because the soap and heat help loosen the fibers. Rub some more until it's the way you like it.
Squeeze out the water. Roll the piece in a towel to get rid of more water. Block the piece and put it in a warm, dry place to finish drying.
Felted pieces can still shrink after they have been processed like this, so treat them like other woolens and wash in cold water.
The library has a book with instructions and patterns called Felted Crochet by Jane Davis. There are also at least six books on how to felt with knitted work.
You can find patterns and instructions, written or on video, online. Put "felted crochet" in the search bar - and happy crafting.