Bradon from Paraportable built an installation using a table covered in copper contacts, two copper-bottomed glasses, a Doepfer Drehbank MIDI controller and the inevitable computer running Max/MSP. It uses the CV inputs on the Drehbank - as the cups make circuits in the table, different voltages flow into it, creating different sounds. No video yet, unfortunately, but it should be on the way. Project Page. (Thanks, Shawn)
Posted by Tom Whitwell. 
