A spectator selects and signs a card, which then gets lost inside the deck. You spread the deck on the table or on any surface, borrow their headphones, then slowly move the headphones on top of the deck.
Surprisingly, the headphones stop and stick to the one card - the spectator's signed card!
This is a must-have for a worker. Suitable for any environment. And because this uses a borrowed object, of course this is very strong and will amaze your audience.