Danger is not Charles Anderson's middle name. That became clear one night behind a catfish-fry house in Mount Home, Ark., when the eatery's owner pulled a gun on him. "He was going to get me for stealing his oil," says Anderson, founder of Golden Fuel Systems, which makes straight vegetable oil (SVO) conversion kits for diesel vehicles.

"Before 2008, it was on a rocket sled to the moon," Anderson says of Golden Fuel's best-ever annual revenue of $1.8 million. When the economy crashed in 2008, so did sales. But the numbers are climbing back up, and in 2011 the company sold $800,000 worth of product.

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