Take a look at the GEN H-4 helicopter, the World's Smallest Helicopter. It is a perfect helicopter for personal use! The GEN H-4 helicopter was developed by Gennai Yanagisawa, 75, of Japan, in the late 1990s. It has two rotors turning in opposite directions to maintain stability, and four engines that enables a 30-minute flight with a top speed of about 56 miles per hour. Japanese Gen Corporation sell fit or about 6 million yen (US$57,140). Watch the video at the bottom, to see it in action.