Meet the man who "had more impact on the atmosphere than any other single organism in earth history" - Thomas Midgley, Jr. Midgley invented leaded gasoline in 1921 to stop cars from knocking. In the process, he created a huge new industry, increased by 500 times the atmospheric lead levels, and was part of a multi-decade coverup of lead's effects that put the tobacco industry to shame [note: article is both terrific and very long] and still continues today. Just a few years later, he invented chlorofluorocarbons, and, with a dramatic demonstration of their safety, usured in an era of cheap air conditioning and social change, as well as ozone depletion. In the end, he was killed by one of his inventions, though it was neither lead nor CFCs that were responsible. He is sometimes remembered fondly, he is more often vilified.