I found some 12 x 12 tiles at a job site the other day that were made up of individual 1" square clear glass tiles with a white layer of paint on back. I also had a dry erase marker. The logical thing to do was turn them into chits for... whatever I want! Here is a
picture from my fledgling blog. It should be fairly easy to find a similar sheet of tile if you want your own. Cheers!