Last year, I began creating a sign for my haunt (pictured at: http://i161.photobucket.com/albums/t239/hawkshillhaunter/Hawks%20Hill%20Sign/completelycarved.jpg ). I used polystyrene and carved out the design with a dremel tool - which I found to be a pain because it melted the polystyrene and packed onto the bit frequently. I've since painted it with a faux stone spray paint. I'm thinking I need a backing on it of some sorts for structural support - plywood maybe? Any suggestions?