Sorry, I don't have a picture, but if you have access to the latest edition of Quilter's Home, there is an article near the front about using zippers as trim. Also shows a quilt with zippers (non-functioning I assume) between the blocks. I was thinking about attaching the zipper behind the binding with only the teeth showing. Had to hunt around to find a place that sold zipper by the yard, but finally found it in an upholstery shop.
Ginny in FL