I show my students several videos on astrology, psychics, etc. at the beginning of the course. One of my favorites is about a guy who did palm reading to pay his way through college. He studied the basic ideas of palm reading so he would sound convincing, though he typically didn't believe in it himself. One day a friend bet him that he would do just as well if he told people the opposite of what he read in their palms. Sure enough, people were still stunned at his 'accuracy!' Hehe, fun stuff.