The Dreamcast video game console had several light guns released as accessories between the years of 2000 and 2003. The official light gun from Sega was released in Europe and Asia, but not in the United States due to concerns about bad press soon after the Columbine High School massacre. Instead, an officially licensed light gun was released by Mad Catz for the U.S. market.
Several Dreamcast games support light guns, as well as various homebrew titles. The light guns work with a CRT TV or a CRT VGA monitor in 640x480 mode.
Source: Wikipedia, "Dreamcast light guns", available under the CC-BY-SA License.