Roy Watts

A fine actress and a timeless beauty but that's not all she was. It's not widely known that she, along with George Antheil, were granted a patent for their idea of frequency hopping for secret communications and a method of making torpedoes harder to detect. The practical applications of this idea weren't realized until many decades after the patent expired but you can thank Hedy Lamarr for your Wi-fi connection and your cellphone conversations.