My favorite is a triple irish chain, with the squares finishing at 1-1/2". On the alternate block, the center square finishes at 7-1/2", which is the perfect size to do embroidery (my embroidery hoop is 5x7"). I cut the center block at 8-1/2 inches; after the embroidery is done, I trim it to 8", so it finishes at 7-1/2".
I love to put embroidered flowers in the blocks (from Embroidery Library), and I'm currently working on one using their flowers of the Bible blocks.
I recently made a baby quilt with nursing rhymes (from DesignsbySick); the center blocks were white, with colorful sashing and a colorful backing. I love combining embroidery with my quilting!