TV illusionist Derren Brown correctly 'predicted' the National Lottery results last week (his prediction was only shown after the numbers were announced, funnily enough).
Though a surprisingly small number of people seem to believe he did it with actual magic, the Great British Public have been busily revealing their stupidity ever since as they try to work out how he pulled off the trick. Best explanation I've heard so far is: "They obviously filmed him doing all the possible combinations beforehand, then showed the right one."