This effect was demonstrated for me at a Brick and Mortar shop. Though I understood the priciple, I really enjoyed the effect.
10 cards are shown, the spectator counts the cards to ensure no extra cards are there. 5 cards are counted and handed to the spectator, and the remaing 5 cards are spread for them to look and remember one. A snap of the fingers and it happens, the 5 cards that they just looked at has dwindled in count to 4, their thuoght of card has vanished and when they count the cards they hold, the 5 has increased to 6 with their thought of card in their hands.
Difficulty from 1-5: 2
There is a sequence and subtle count that needs to be learned and once you can master that, this is a beautiful thought of card to hands.
http://www.mjmmagic.com/store/crossed-t ... -7671.html