I attended a local show last weekend and their challenge quilt was also a paint chip challenge. There were some really nice quilts and they did a great job matching fabrics on their paint chips, with quite a variety of patterns/blocks. They were also allowed to add either black or white to their chip colors, but no other colors. It made for a nice display of monochromatic quilts. Another show I was at, everyone received two pieces of fabric that had to be incorporated in some way into the quilt, even in a very small way. I think one was a zebra stripe and the other a bright floral. It was fun too look for the fabrics in everyone's finished work. Another challenge I saw, the quilt had to incorporate letters or words in some way, a maximum of two inches high. There were a lot of fun interpretations of themes with that.