Steve Wozniak produces and uses his own two dollar bills. You've seen novelty $2 bill note paper. It's often gummed for easy removal and usage. Same with these bills, but these are legal tender. Woz goes on to detail other situations where printing interesting things has led to fun and profit.
"They were new money, without a doubt: so new it shrieked. Their clothes looked as if they’d covered themselves in glue, then rolled around in hundred-dollar bills.” ~ Margaret Atwood
Note Worthy: [guardian.co.uk] Global economic meltdown, the euro crisis and Occupy protests – this year has been dominated by financial issues. But what is money anyway? We invited writers and artists including Jonathan Franzen, Margaret Atwood and Naomi Klein to invent new currencies and banknotes for a changed world.
Man turns $1 bill into over $11 via Ebay. No it's not old, it's just a used 2003-series bill that's not even in very good condition. It does has an interesting serial number, though. As does this other $1 bill also on Ebay with a current bid of $11. Of course if your dollar bills don't have particularly rare serial numbers it doesn't mean you can't Ebay your way to profit.
secret pictures of 9/11 attacks found on $20 bills. Possibly the dumbest conspiracy theory to date. I can't beleive I'm posting this.