Two guys are walking in a rough neighborhood when someone jumps out from behind a car, pulls out a pistol, and demands, "Give me your wallets, NOW!"

The guys, pretty much expecting this, sigh and pull out their wallets. One guy opens his wallet and shows the thief that he had no cash and no credit cards.

The other guy opens his and grabs a bill, handing it to his friend. "Oh, hey, here's the $20 I owe you."