When we think about a calculator, especially a mechanical one, it appears to be a complex machine with a set of advanced mechanism. But the fact that the first calculating machine, a pascaline, was dreamt by a child and put together by a teenager, is simply mind-blowing. Back in 1642 a French wunderkind named Blaise Pascal started his engineering experiment and created a fully mechanical calculator to make his father’s job (tax collector) a bit easier for him. Other incredible examples of technologies, which were invented by wunderkinds and young scientists, may be found in this interactive video presentation: https://www.youtube.com/watch?v=_x_LuWWgA3Q We have reviewed the history of such incredible inventions: - waterskiing; - cheap medical testing systems; - flashlights, which are powered only by human body heat.