With your back turned, your spectator stacks the dice in any way he wants.  After turning around, you are able to correctly guess the number of visible spots instantly!

Going further, with your back turned again, your spectator rolls a die on the table and remembers the number he landed on (a completely random choice).  Without ever looking at the die, you reveal the number he is thinking of!

Includes instructions via download.  Condition unused, like new.