Two lawyers are in a bank, when, suddenly, armed robbers burst in. While several of the robbers take the money from the tellers, others line the customers, including the lawyers, up against a wall, and proceed to take their wallets, watches, etc. While this is going on lawyer number one jams something in lawyer number two's hand.
Without looking down, lawyer number two whispers, “What is this?”

To which lawyer number one replies, “It's that $50 I owe you.”