One of the most unsuccessful peripherals was the Sega Activator, a 1993 peripheral based on a musical instrument called the Light Harp conceived by musician Assaf Gurner. Marketed as a new type of martial arts simulator, it is an octagonal device that lays flat on the floor and reads a gamer's physical movements. As the player moves, infrared laser beams trigger which is translated into game inputs. The light beams are easily distorted by a non-flat ceiling or obstructions such as blades of a ceiling fan or light fixture. Along with pack-ins Eternal Champions, Mortal Kombat, and Street Fighter II: Special Champion Edition, Comix Zone, Mortal Kombat 3, and Greatest Heavyweights of the Ring were all developed to support the peripheral. It can also be used as an alternative to the standard three-button controller. The Sega Activator was dismissed by consumers due to "unwieldiness and inaccuracy." The $80 price point also contributed to the peripheral's lack of success. The Sega Activator was ranked the third worst video game controller ever made by IGN editor Craig Harris.
Source: Wikipedia, "Sega Activator", available under the CC-BY-SA License.