One thing I like to do with them is 3D bow ties, which need 2 of one color and 3 of another. Unfortunately, I am not finding those right now. I guess I'll have to make one. The pictured quilt is called (among other things) Underground Railroad. Lots of patterns use 4 or 9 patches, which do not have to be just 2 or 3 colors. A single, double or triple Irish chain can be done scrappily either with plain alternate blocks or as a setting for other blocks or prints. If you browse through traditional patterns, such as those on
www.quilterscache.com, you will find lots of uses. I also use lots of them in HSTs, either with a single alternate color or doing a light/dark variation. Carpenter's wheel can be made with them also.