Woosy - I got really interested in op art and spent a lot of time looking a art from that period. I decided to try doing a quilt that would mimic some of the art. I used a really cheap black and white stripe to make the checks and sewed the vertical seams closer together and then farther apart to get the wavy illusion. I didn't know if I had achieved my aim until I finished the piecing and stepped back from the design wall to have a look. The border is a great retro print that sets it off. Everyone hates it but me. I used a pantograph to quilt it at first, but then I had to go back and stitch in the ditch to get the right effect.