Thanks to Chloé in the Noise Gear comments for letting me know about the Cracklebox - a pocket-sized analog synth which is controlled by the conductivity of your fingers. It was designed in Amsterdam in the late '60s. About 4,000 of them were sold in the mid '70s, and this batch were re-issued in 2004. Obviously it sounds [800k mp3] pretty much bonkers, but it looks very cool and you can buy one for €50, or build one yourself. Just don't get too into it, or you might end up like composer Mark Applebaum, who earlier this month performed "5:3", a piece for 8 cracklebox players and 2 amplified dice rollers at Stanford University (details).