Touring the software/pro audio building, I ran across these guys - Voltage Modular. It's actually a pretty slick little interface, and its mapping of MIDI to controls helps keep it visceral. But the interesting thing: there is an SDK (of sorts) along with a device builder that makes quick work of the user interface, and ties it a to Java-based audio engine. Freakin' insane - and worth checking out as more is revealed.
So exactly how much more modular are we going to get? More please!!!