This mod was sent to me by fellow bender and experimental musician Allerian, is called the Copper Box. The case supposely came from an old hand reciept machine. The control surface features four copper touch plates that are tied to the onboard oscillator circuitry changing the resistance levels when they are touched by skin thus effecting the oscillators. Copper happens to be the best conductor trailing only to silver, being far cheaper makies it a great choice. I tend to use just plain old screws with their tops sanded quite well to create a rought conductive surface.
The conductivity depends on oil levels of your skin and can be improved by wetting the skin. Other things that are quite interesting to experiment with are flourecent lights and “plasma” lamps, the ones that have arcs of energy in them. Electrons get picked up by the contacts and turned into various noises. For some reason this mod reminds me of the Mars Rover, I dunno maybe its just me.