Have you ever heard of Zentangles? The website says, "Zentangle is an easy to learn method of creating beautiful images from repetitive patterns." There to books, tutorials, and a gallery of pictures. It's a unique idea and I think it would be fun to try! Here are some examples by Rick Roberts:
Used with permission.
The Quilt Rat Jill Buckley makes similar designs called Doodles. She combines this quilting, sewing, and other artistic pursuits.