I have only seen Derren Brown a couple of times, he's interesting but I'm not a particular fan. He's an illusionist come hypnotist come magician type chap. I did happen to see the program with the instant conversion. If I remember, he went around pretending to be a faith healer to convert people. From what little I've seen he doesn't claim extraordinary powers, and often explains the logic behind his "tricks".
Just googled him and found this page with more video footage and stuff
I asked the question earlier in this thread, "If O Sensei were alive today performing similar feats, how would we be reacting here"? I understand, since he's not here and most of our exposure is limited to a few tapes from AJ, it's a hyperthetical question. I'm just curious as to whether he would suffer the same kind of reaction, or whether we would all be still be doing the art?