My wife came across this, and she thought it might be helpful to me.
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I figure you could make a sheet of railroad and highway signs, billboards, and advertising then when you need them, cut them out and stick them on. I have NOT tried this but I sure will
Charlie

That is a great website to browse. Some people are making some amazing things these days. I saw one article on there for making your own laser cutter out of a flatbed scanner.