A couple years ago I participated in a challenge involving 17 people. Each month we brought in 17 identical 9 patches, and traded. The only requirements were: unfinished size 3.5", bright colors and neutrals, no civil war or pastels, and the dark had to be in the 5 spots (4 corners and center). We could make extras and trade. We were to make a quilt and share at our Christmas get together. They were all beautiful and so different.