Another idea would be to use his already suggested technique of purchasing different types of cutting boards, cutting them to the appropriate sizes, and gluing them together in designed patterns. The cutting boards at places like WalMart aren't very expensive, but come in a suprizing variety such as hard rock maple end cut, bamboo, and oak. By mixing the three different woods, you could come up with a visually striking, and highly useful end product. Also, by using ready made boards as the basic building material, you could change the thickness of the end product by simply laminating another board on top of the first board. I believe this sould also inhibit warping by creating a laminate joint on the horizontal plane relative to the board., or, better yet, glue and end grain board to a horizontal board to give it structural integrity in two planes. Of course, the end-grain board woult have to be on top.
Just an idea.
Seeeeeeya; Goodweed of the North