That's actually a really awesome idea to use against all the scammers out there.
When they want money for whatever reason (processing fees for your millions of dollars in some bank in nigeria or whatever), mail them a big fat stack of Monopoly Money and a note that says "Do Not Pass Go, Do Not Collect Two Hundred Dollars."
Edit : when they complain about the "money" tell them that (the monopoly money) it is the only currency used in the United States anymore (or your particular State), and that Money Orders have been banned as well.
