Marion Systems MSR-2
The Marion MSR-2 was designed by Tom Oberheim and so it is known for having the 'Oberheim sound' packaged inside a compact single-space rackmount module with modern digital reliability and MIDI implementation. Despite its rather harmless and simple appearance, the MSR-2 allows for some fairly complex but intuitive programming. The filters, envelopes, LFOs and other parameters are very analog-like in their sound and editing methods. The module is also 16-part multitimbral. And external inputs route a signal through the envelope and filter sections. The MSR-2 is rare but definitely worth checking out.
Demos & Media
Images from Perfect Circuit Audio.