Ruby on Bells: The Ruby-Powered Musical Glass Playing Machine
Ruby on Bells is a demo of the Madrona fork of RAD (Ruby Arduino Development) itself a Ruby bridge to Arduino, an open source electronics prototyping platform. Powered by a simple Ruby script, a set of glasses are hit by small mallets on servos, resulting in a Philip Glass-esque cacophony. It's a compelling demo, and if physical computing intrigues you, the tools available to Ruby and Arduino developers are now mature enough to bring interesting results within easy reach.
A longer "behind the scenes" video explaining how it was put together and how the code looks is also available. The code used is a very simple Ruby-based DSL. Couple this with Giles Bowkett's MIDI generator and you could have a lot of fun.