I have recently been bitten by the circuit bending bug again. It started with wanting to make a dub siren and getting in touch with Alex at getlofi for some boards. The next thing I know I'm getting into trouble for improving my kids toys. But the way I see it its a win win situation ;)
I did do a number of midi hacks years ago, when arduinio was just a dream.
One person who I know from around this time that has kept going and is now producing some amazing work is Gieskes. He is creating a crazy array of visualisation techniques that use physical objects manipulated by motors, alternating light frequencies and em i suppose for want of a better description - magnetic puppetry. An object of great desire he has created can be found here. He also makes damn good noodles and is always a welcome visitor to Ticket acres.