20. Eye Toy
Essentially a webcam for your PlayStation, the Eye Toy is actually a forerunner of the Kinect, using color, sound and motion as its control inputs. It's been a staple for Dance Dance Revolution, MLB The Show, and other casual PlayStation games for years, but rarely gets any love for its place in the evolution of motion control (or the fact that it sold more than 10 million units worldwide.) So here you go, Eye Toy: Good job. Now please get off our TV.