Browsing around CDM I found this, a thing of complete beauty…
Master chip musician Gijs Gieskes has outdone himself this time: his second Walkman tape sequencer controls the Game Boy music cartridge LSDJ via various knobs and circuitry. His typography is utterly mysterious (in other words, completely illegible), so here’s my translation:
It has got LSDJ sync, because it uses gwems lsdj pitch control as master clock . . . the red potentiometers determine the playback speed of the cassette deck, and the yellow potentiometer controls the clock speed.
In other words, the sequencer he built controls both a Walkman tape deck and a Game Boy.
Now how cool is that!