I'm a bit of a currency naturalist: I round bills up, mark them, and release them back into the wild. That even goes for two dollar bills, which many Americans believe are no longer made (they are; in fact, series 2013 is in print now). Because the two is in such low circulation, if you ask for them at the bank like I do, you will see some very old, very well-preserved currency.
Only on a two did I have much of a chance of finding this story. Everything I know for a fact comes from that very bill, which I have pictured here. A two from series 1976, in fairly crisp condition, with a note scrawled across it in black ink. The handwriting crosses over dark portions of the bill's design, there's at least one word crossed out, and it's not very legible in the first place, but this is what I think it reads:
"To the [Checkers or Cheeses or Russo or something] Deli
Congrats on Year #1
Best of Luck For the Future"
[squiggle or signature]