You present a few pieces of paper that are blank on both sides and cut to the size of "bank notes". You explain that you are going to play one of these "bills", and you place it on the table. Then you shuffle a deck of cards and place it in a case that has a slot on the back of it. Using it like a dealer shoe, you deal the cards one by one, until the spectator says "stop". The name of the card then appears on the bill left on the table.

Demo

Very Easy to perform - The Spectator can say "stop" at any time - The cards can be seen flicking by through the slot in the case as you deal the cards - you can use you own case to perform the trick - Extremely impressive, even when performed on confirmed magicians - Ideal in combination with a trick where you have to force a card in "laboratory conditions"