Penny

A penny dropped from the Empire State Building will not kill a person or crack the sidewalk. The terminal velocity of a falling penny is about 30–50 miles per hour (50–80 km/h), and the penny will not exceed that speed regardless of the height from which it is dropped. At that speed, its energy is not enough to penetrate a human skull or crack concrete, as demonstrated on an episode of MythBusters. As MythBusters noted, the Empire State Building is a particularly poor setting for this misconception, since its tapered shape would make it impossible to drop anything directly from the top to street level. MythBusters also pointed out that this doesn't mean that dropping coins from high altitude is safe. It might still cause harm.