Few of us have the means or the smarts to exact revenge on a shark that has nearly bitten us in two; John Perry, however, had just that. A consummate entrepreneur, Perry founded Perry Submarine Builders, based on his original idea for a “small submersible that would allow a diver to hunt sharks safely."

The son of Florida newspaper owner John Perry Sr., Perry inherited the business after receiving his Harvard M.B.A. in 1940. According to the Palm Beach Post, he went on to found and run Perry Cable, Perry TriTech, Perry Technologies, Perry Baromedical and Perry Oceanographics. The energetic inventor still made time to form a small research company, Energy Partners, dedicated to finding an environmentally friendly, renewable energy source. Perry was the type of person who sold his company because it was doing too well. He died in Gainesville, Ga.