Speeding is easy to do, and like it or not having someone else in the car nagging you about it actually can help. What to do if your mother is unavailable? Check out Slow Down in the App Store. It's a product of the Belgian organization OVK, Parents of Children Killed in Road Accidents, and it has a very simple idea: if you drive too fast it slows down your music, as demonstrated below. Cross the limit and your thumping beats get run through molasses, but get back to a legal speed and Joanna Newsom's lilting highs stop sounding like a zombie's baleful lamentations. We're not entirely sure whether the app wo
