Here's a "heads-up" to all my fellow CGN'ers. Princess Auto is selling a 40 lb. bag of ground walnut shells for $30.00 + tax. They sell it for use as a coarse sandblasting medium. Has anyone else twigged on to this or actually used it? If so, be a sport and give us a performance review. I'll be getting my new tumbler this weekend, and giving it a work out, so if no one else chimes in, I'll be letting all of you know how it works out. This just seems to me to be a fantastic deal, and I'm not so petty as to keep this to myself.