Lonnie Johnson, age 70, was always a maker. As a child, his experiments with rocket fuel nearly burned down his house. While in high school, Johnson was the only black student to enter the Alabama science fair; his entry, a pneumatic robot named Linex, took first prize. Johnson went on to earn engineering degrees from Tuskegee University, worked on the stealth bomber for the US Air Force, developed nuclear power systems for NASA's Jet Propulsion Laboratory, and has since founded two tech companies -- one that develops solid state batteries and the other focused on thermo-electrochemical converters with green energy applications.
Oh yeah, he also invented the Super Soaker.
From William Broad's 2001 New York Times profile of Johnson :
On his day job in 1982, Lonnie G. Johnson, a 32-year-old aerospace engineer, was preparing an interplanetary spacecraft for its atomic battery. But he dreamed of inventing something that would change life on earth.
He often worked at home as his wife and children slept. One weekend, while tinkering in his bathroom, Mr. Johnson hooked up to the sink a prototype cooling device.
Meant to run on water, it bore at one end a length of vinyl tubing and a homemade metal nozzle. The rest, as they say, is history.
''I turned and shot into the bathtub,'' he recalled. The blast was so powerful that the whoosh of accompanying air set the bathroom curtains flying. ''I said to myself, 'Jeez, this would make a great water gun.' ''