EVEN the nicest of people can become real devils when they’re seated behind the wheel of a car. Stephen Dubner, co-author of the new book Super Freakonomics, made this observation on his New York Times blog after a policeman sent him an e-mail, asking, “Why is it that driving brings out the worst in people?” Instead of answering the question himself, the author decided to invite readers to respond. Here are some of the most interesting answers: