Super Game Boy television commercial.
http://darth-azrael.tumblr.com/post/158478059767/vgjunk-super-game-boy-television-commercial
The Super Game Boy was an adapter for the Super Nintendo that allowed Game Boy games to be played on the system. In addition to allowing you to use the SNES controllers and a TV for display, it also allowed for certain enhancements if the games supported them, including adding color. The Super Game Boy supported original Game Boy games and some Game Boy Color games.
Essentially, the Super Game Boy contained all of the Game Boy hardware with the SNES just being used for controllers, video output and any supported enhancements. It came in the form of a cartridge that plugged in like any other cartridge and had a slot on top in which to insert a Game Boy game.
If you were a Game Boy fan and owned an SNES then it was definitely worth the $59.99 to get one of these. This was the first commercially available Game Boy based add-on for a Nintendo console but it wouldn’t be the last. A similar device would be released later on the Game Cube that also supported Game Boy Advance games.
Above is a clip from a commercial for the Super Game Boy.