The Back Palm
The magician holds a card, flicks his hand and the card disappears, another flick of the hand and the card reappears.
How It's Done
Take any card and hold it pressed between your thumb, ring, and middle finger. With your thumb, slide the card over your ring and middle finger and grab it between your pinky and index finger, on the back of your hand, so that the card is hidden behind your hand. To make the card reappear, slide your index finger back and grab the card with your thumb and pull it into the front of your hand.