It’s called the Guitar Boy.
The device works as both a fully functioning guitar and Nintendo Game Boy, or both at the same time. The Guitar Boy’s A and B buttons double as volume and tone dials for the instrument.
The Guitar Boy has been loaded with a variety of classic Game Boy and Game Boy Color titles including Super Mario Land and Ballistic. You can choose whether or not you would like the guitar to emit sound from the Game Boy games.
See the Guitar Boy in action below. [via The Daily Dot]
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