I just purchased Insight because I had recently seen a mentalist do a similar illusion. While the Insight gimmick was quite inventive, my hopes of learning how the illusion I experienced was accomplished were not realized. In the show I saw, the performer asked for three volunteers and gave us all pieces of blotter paper and small envelopes along with a golf scoring pencil. He then asked me to write the last 4 digits of my social security number on a piece of blotter stock using the golf pencil. I folded it twice and inserted it into the envelope that was given to me. The envelope was not gimmicked in any way. I licked the envelope and sealed it closed. Handed the envelope back to him, he wrote a number on it and he gave mine plus the others to a spectator to hold. When it was my turn, he asked me to visualize the last four digits of my social security number in front of me and above my head. I was instructed to imagine one of the numbers and grab it. He asked was it an "8". And it was. He then asked me to reach up and imagine grabbing one of the three remaining numbers. He asked if it was a "3". I announced it was not. He quickly corrected himself and said it was a "2". He was just a little off. I told him it was, in fact, a "2". He then grabbed a large sketchbook and wrote something in felt tip pen. But didn't reveal it yet. He asked the spectator for the envelope, which had been ripped open. Although I did not see the spectator tear open the envelope, she claimed she had just done so. He took out the folded paper and asked someone to read it. Then he showed what he had written. They were both the same 4 digits. He was also correct in getting the name of a woman's first boyfriend and another spectator's birthplace. Now I dabble in illusions and magic and it isn't often I cannot discern how something is accomplished. But this time, there was no way I could figure it out unless the spectator holding the envelopes was a confederate and was in some way communicating with the performer. But even then I would have noticed her opening the envelopes and reading the contents, which were folded up inside and written in light pencil. However it was done, it was a great illusion.