Korg MS2000 by plexicube
In 2005 I traded a Nord Rack for the MS2000. While I enjoyed the Nord's interface and sound, I had need of an integrated but compact unit and was intrigued by the MS2000's modulation sequencer. This internal sequencer let's one select 3 voice parameters to be modulated, in either a smooth or quantized manner, triggered by keypress and (potentially) synced to MIDI clock. It can serve the purpose of a highly programmable loopable envelope as well as a simple, yet transposable, phrase sequencer. Using the MS2000's audio input this makes the MS2000 a very affordable filter sequencer for drum loops, guitars, etc. The fact that the filter is multimode and is resonant in LP, HP and BP modes makes this doubly so.
Another great feature of the MS2000 is its modulation matrix. This is very reminiscent of the Oberheim Matrix series modulation matrices where each mod slot has a source, destination and amount. While the MS2000 has a more limited number of slots (4), sources, and destinations than the Oberheim it is laid out very thoughtfully and is a great introduction to more advanced modulation for the beginner; first understanding an LFO modulated by an envelope was an eye opener for me personally.
The MS2000 has a definite voice, which you may or not like. It is raspy and definitively not 'analog' when its filter is wide open, and its resonance is not volume compensated, but the combo of the mod sequencer and the matrix make for many long evolving tones. In this regard, I think it has some kinship with the DSI Evolver.
Cons? Cheap PCB mounted knobs. Lack of aftertouch. 4 note poly (not a hindrance for me, as it *feels* more like a mono than a poly synth anyway.)
These can be had cheap these days, also contain a nice sounding vocoder, and can be polychained together (though sadly not with the MicroKORG.) Really great value for the price.