Amateur inventor Tao Xiangli prepares to operate his homemade submarine in a lake on the outskirts of Beijing September 3, 2009. Tao, 34, made a fully functional submarine, which has a periscope, depth control tanks, electric motors, manometer, and two propellers, from old oil barrels and tools which he bought at a second-hand market. He took 2 years to invent and test the submarine which costs 30,000 yuan ($4,385). REUTERS/Christina Hu (CHINA SCI TECH ODDLY)