Presence of mind!!
Santa and Banta were in a bank, when armed robbers burst in. While several of the robbers take the money from the tellers, others line the customers, including Santa ands Banta, up against a wall, and proceed to take their wallets, watches, etc. While this is going on Santa jams something in Banta`s hand.
Without looking down, Banta whispers, "What is this?"
To which Santa replies, "It`s that Rs 500 I owe you."