Here is a David Blaine trick for you from one of David's televised magic shows.
You have a card selected and signed by a spectator. The card is then put back into the pack by the spectator and you then shuffle the deck.
You appear to have problems locating the signed card but keep picking the wrong card over and over.
Finally, you seem to have some discomfort in your throat you start coughing only to regurgitate the spectators card, now tightly folded and bearing the spectators signature!
