A mystery quilt is the fun way to make a quilt and keep the final look a "mystery" until the end. Done one step at a time - seems often to be a weekend or holiday. If you do a search you can find many and there are several books out. Billie Lauder, Rita Fishel are ones I know of. Judy Laquidera has several on her site Patchwork Times that I have really enjoyed. Animas Quilts by Jackie Robinson has an ongoing mystery that will be for the entire year. Chris and Barbara Quilts has Mystery Mondays with a new one to start soon. Eric Homemade has a current mystery going.