Once done you remove a giant playing card from an envelope. With dramatic flair you turn the card around and there is the spectators card! Along with the other 51 cards that are printed on it (this gets a great laugh).
But wait there's more. Offer to repeat the effect, only this time you take out a marker pen and make a large X on one of the 52 cards. Your spectator is now requested to think of another card and when you turn the giant card around your spectator's choice is the only card with an X on it!
This trick may be instantly repeated if you wish.