The Super NES Mouse is a peripheral released by Nintendo in 1992 for the Super Nintendo Entertainment System (SNES). Originally designed for use with the game Mario Paint, the SNES Mouse was sold in a bundle with the game and included a plastic mouse pad. Soon after its introduction, several other titles were released with Super NES Mouse support.
Although this device closely resembles and mimics the functionality of a two-button computer mouse, it was smaller than most computer mice of the time and had a significantly shorter cord than the standard Super NES controller.
Source: Wikipedia, "Super NES Mouse", available under the CC-BY-SA License.