About a year ago I spent a day mono printing fabric. I did one series of black, red and white fabric. I chose one of these fabrics as the fabric for my case. I loved the strong graphic quality of the fabric and I thought it would work well as a MP4 case.
I next cut a small hole part way down the fabric to put the MP4 jack though. I folded the fabric and stitched down the side and sewed on a cord an voila I had a a very simple case to protect my MP4 player.