IMAGINE RESTORING A SIGNED CARD IN FRONT OF A SPECTATOR'S EYES!
The spectator selects a card. The magician makes a mark on the corner of the card. The spectator TEARS the card and signs the larger, remaining portion of the card. The magician SHOWS BOTH SIGNED PIECES OF THE CARD (spectator's signature and magician's mark). The spectator puts the small piece into the magician's mouth. The magician just blows on the card and the card is magically RESTORED RIGHT IN FRONT OF THE SPECTATOR'S EYES! AND, the restored card contains BOTH the spectator's signature and magician's mark!