The Korg MS-50 - modular in design and at the height of the MS-series synthesizers. This keyboard-less expander type module is completely patchable and uses Korg's Hz/V type of CV and Gate for control with other synths like the MS-20. There are lots of knobs and patch points on this one... The MS-50 is still a single VCO monophonic analog beast but offered more patchability and power than any other MS synth. Other features include a ring modulator, voltmeter and sample & hold. It was also designed to complement the SQ-10 sequencer. It has been used by The Chemical Brothers.
Demos & Media
Images from a Korg product brochure and Perfect Circuit Audio.