In the early 1900s, Florence Lawrence was one of the most recognizable women in America. She starred in over 300 silent films and is credited as being the world's first film star. But in addition to her Hollywood hustle, Florence was also a bit of an inventor. In 1914, she created a mechanical signaling arm for cars, a precursor for the modern-day turn signal. At the push of a button, a flag would rise on the back bumper indicating if the driver wanted to turn left or right. Sadly, Lawrence never registered her design and she was never credited for her invention-nevertheless, her contributions to the automobile industry will live on forever.