The newly-released Organelle M now comes with a built-in speaker and mic, MIDI jacks and battery power, so you can play on the go. It's also got a pepped up 1.2GHz Quad-Core processor, double the RAM and it comes with a USB WiFi adaptor.
What's really exciting, though, is that it's now driven by a Raspberry Pi, instead of the original solid run i.MX6. This isn't a mysterious device powered by obscure components, but rather a digital synth with a pretty active community of musicians building custom patches for it -- the sort of thing Korg is probably hoping for with its digital oscillators on the Prologue and Minilogue XD. Get the Organelle M for $595 from critterandguiatri.com.