Sam Battle of Look Mum No Computer, the mad sonic scientist who brought us the Furby Organ, has done it again. This time, he turned a Sega Genesis/Mega Drive into an awesomely retro-sounding synthesizer.
The Sega Mega Drive included a Yamaha YM2612 six-channel FM synthesizer chip under the hood. Sam broke that out to create his synth which so epically invokes that iconic, often cringe-worthy, 80s synth sound.
On his second YouTube channel, Look Mum No Computer But More Serious-ish, he goes into more detail about the YM2612, the Sega Drive, and putting together the synth.