The other most populous item in the house besides bears, licence plates and books, are stars. These were made from salvaged plywood I got two doors up from me. A neighbour used it as a cement mold and it was too warped afterwards to do anything structural with it. I drew these roughly 1' stars freehand and cut away with a jig saw. A few coats of indoor latex and there you go, a nifty op-art mobile.