This is referred to as the "holy grail" of card tricks. I don't think people could figure it out, but it might be fun to try. Here's a youtube video of the trick. I was reading some magician's forums, and there were various speculations about it possibly involving trick decks and memorizations. Even so, the trick, as performed, doesn't seem like any of that would help. The most obvious solution would be that there are in fact stooges. But the first example involves British tv personalities. From what I've read, Berglas perfomed the trick for other magicians who were stunned. The man performing the trick is Berglas's best friend, supposedly one of the only other people who knows how its done. It's interesting, because by all means, it looks completely impossible. Any thoughts?