This Axon demo recorded for BassPlayer.tv is incredibly cool: it's a realtime pitch-to-MIDI converter that handles chords. Plus it can apparently detect where on the guitar you're playing, right or left hand, and change patches accordingly. So the top half of the fretboard can be a different instrument from the bottom, and each pickup can be a different instrument. Towards the end, the demo presenter plays a complete MIDI jazz trio with drums, bass, and Fender Rhodes organ, all triggered from what looks like a PRS guitar. They say it'll work almost as well on a bass as on a guitar.
Of course, it also runs $1,200, and it still requires installing a special hex pickup that listens to each string individually. It costs a lot to live this free, Wayne.