As I brought up in another thread with no replies as of yet - See Derren Brown - Mind Control. The things other people can do with your mind is incredible. I would agree with J that hypnotists cannot make you do something you don't want to do, but of course, you have to be honest enough with yourself to know that what you THINK YOU WILL DO, and what you will actually do under abnormal circumstances are completely different things. Most people have a very deluded sense of self, and will actually act the considerable fool, given the opportunity. Personally though, I don't think your friend has much to worry about. If hypnotists could shake people down for money (or sex, or whatever) against his/her will, we'd hear about it.