Harvard psychology professor Dan Gilbert spoke at TED2004 on some of the principles in his book, Stumbling on Happiness.  He discusses a number of very interesting ideas, including the fact that we are generally poor predictors of what truly does make us happy.  Towards the end of the talk, he discusses how people who have restricted freedom and fewer choices are often happier than people who have unlimited choices.  If true, this might explain some of the appeal of cult-like groups.

Dan Gilbert