Ray Dalio, Connecticut
Dalio's $18.4 billion net worth comes from hedge funds. He's the founder of the largest hedge fund firm, Bridgewater Associates, and it manages $160 billion in assets. He started playing the stock market at 12 years old and then launched Bridgewater from his modest NYC apartment in 1975.
Robert Gore & Elizabeth Snyder, Delaware
Gore and Snyder can thank Gor-Tex for their $885 million. The materials firm W. L. Gore & Associates was founded by their parents in 1958, and it manufactures everything from human body implants to outdoor weather clothing. Robert invented Gore-Tex, a lightweight waterproof fabric.