THIS IS CLEVER!

A spectator chooses a card, which is wrapped in a white handkerchief and laid on the table.  The magician explains he will pound the card with his fist and it will pass through the table to the floor.  After a few good whacks, nothing seeming to happen, he asks the spectator to open the hank.

The card is still there... but wait!  When the card is picked up it is found to be blank and the face is now PRINTED on the handkerchief!