Setting up Ruby access to MIDI In opened up a lingua franca of entertainment hardware. As an example, I wrote a simple script to open a new browser window on BoingBoing by hitting the center button on a Nintendo WiiMote.
Here's a video. Fair warning, I made it late last night and there's some rambling, some cursing, some poor lighting, and some background noise (specifically Otis Redding, Wilson Pickett, and a feng shui water fountain).
To use this code, you'll need to install and set up WiiToMidi. OS X only, sorry.
Of course the real purpose here is not, hey, look, you can launch BoingBoing with a WiiMote. The real point is hey, look, you can link any arbitrary Ruby code to any arbitrary MIDI hardware, and the list of available MIDI hardware is pretty vast.
Check it out:
This is some simple code. You can process input very, very easily. The range of hardware and software that supports MIDI is remarkable; this is more than just Archaeopteryx.