The log cabin quilt pattern has always been one of my favorites. It's been beautifully adapted to crochet in this pattern from Annie's Attic. Here are two examples of two color sets. I love both but even though I'm a purple fan, I like the traditional green and red color combination better. But this would be fun to experiment with any colors you choose.
This is one of many patterns I'm listing that are based on traditional quilt designs. See the full listing at Etsy.