[whiddershins]

The grandfather of this exploration is Moldover and for the purposes of this discussion ignore his current tendecy to involve an electric guitar in his sets ... a recent development.

http://moldover.com/

http://vimeo.com/moldover/live-at-future-everything-excerpts

He ended up designing and building his own controllers using arcade buttons.

Since this is hacker news I'll point out the whole investigation is largely a technology issue. Many studies have shown that expressiveness of great instrumentalists rests on incredibly small timing variations, which ARE NOT random. Because of latency and more especially jitter in the hardware/software interface true virtuosity is either very hard or impossible to develop using most currently available tools. What the actual acceptable level of machine induced random variations are is a much debated point. This is why I pushed Lippold Haken so hard to increase the sampling rate of the continuum fingerboard to its current sub-millisecond levels. The underlying technology of the madrona soundplane can be implemented at audio rate, which, by definition, should be fast enough to obviate this need.