At the height of her Hollywood career, actress Hedy Lamarr was known as "the most beautiful woman in the world." For most of her life, her legacy was her looks.
But in the 1940s in an attempt to help the war effort she quietly invented what would become the precursor to many wireless technologies we use today, including Bluetooth, GPS, cellphone networks and more.
The Navy classified the patent as top secret and it remained untouched for years. But after World War II, the Navy was interested in developing a so-called "sonobuoy" that would use sonar to detect submarines in the water and transmit the information to an airplane above. However, it needed a way to jam-proof the signal between the buoy and the plane.
They resuscitated the idea of frequency-hopping and built it into the sonobuoy. And after that, the whole system just spread like wildfire. The military and private companies all started developing their own technologies around Lamarr's invention. Today, vestiges of her frequency-hopping technique are found in most digital devices that communicate wirelessly.
Lamarr's contribution was "lost in the noise" for decades. In the 1990s when she was in her early 80s, she was finally honored. By phone.