RE: Flat Tire
Just an Idea, I have never done it, but could you just cut a tiny slit in the tire and fill it with some of the expanding foam for sealing windows. I know they make a low expansion kind that would flow pretty well into the tire but not put so much pressure as to damage it. You can get it at most any Lowes, Home Depot, or hardware store, I think even Wal-Mart carrys it.