Last night at Eyebeam, resident Brendan Byrne gave a talk on his project Destiny Clock (formerly, Theseus), a music interface/installation/environment that sends MIDI notes to Ableton and triggers sounds. Essentially this is a modular, patchable computer, with components (sequencer, multiplexer, clock divider, logic gates) that the user connects in various ways by means of patch cables of ordinary thin wire. The design is extremely elegant but the output is bottlenecked by being limited to a stream of on-off notes. Patching changes the sequence, speed and volume, but the device is not sending MIDI CC commands to affect timbre, envelopes, effects, or other typical aspects of electronic music. Also, because the computer components are unlabeled, you aren't really learning much about computation.
Byrne might be cut slack for these limitations except that, in his slide talk, he posed the interface as a challenge, or alternative, to Eurorack-style modular synthesis. He showed examples of "Eurocrack" addicts whose homes have been taken over by their gear purchases, by way of contrast to his modest circuitboard (about 8 x 12 inches). This was kind of unfair -- there might be some middle ground between those lost souls and what he's doing.