Crazy that I missed that. Neighbours had an Atari ST and a friend would sometimes come with his MOOG synthesizer and we'd hook it to the ST but we didn't know

Crazy that I missed that. Neighbours had an Atari ST and a friend would sometimes come with his MOOG synthesizer and we'd hook it to the ST but we didn't know about MIDI hacks to play multiplayer games. Now by default these home computers often had two joystick ports and to be able to play I-don't-remember-which-game we hacked some additional dual-port thinggy on a little PCB we'd hook into the ST's parallel port. This allowed us to play four players at the same time, each with our own joystick, on a single ST / monitor.