Inside Thoughts by Haim Goldenberg

"Inside Thoughts" is a brand new way of predicting. It is smooth, simple and has a great range of possibilities. You can predict almost everything with it, from simple numbers and cards to countries, brands, and even corporate mottos. 

This amazing self-working tool can be used as a brand new act, or it can be adapted to your existing repertoire. Either way, it will serve you well. "Inside Thoughts" is an innovative product that reinvents itself from prediction to prediction and enriches any kind of performing. 

You ask a volunteer merely to think of any one digit number. Then ask him to speak out loud so that everybody can hear him (of course you can invite him to change his mind as often as he chooses). Let's say he chooses the 4 (as always you make sure everyone agrees that it was a completely free choice), you then take the envelope, which was laying in full view the entire time, and pull out of it another, smaller envelope. As you turn the smaller envelope upside down a note falls into your hand. On the note is written the number 4.