when we do shows, we use a tv hooked up to a laptop that cycles threw before and after pics, we always give away bottles of spotter, and have a drawing for email/address capture. And we actually give away what we are raffling off. go figure. some years it works great others it doesn't, but always give stuff away. and expect people to snark and say "i have a bissel", or "does this spotter work in my at home machine", and be prepared to deal with some crazies.