Pipsqueak

The Pipsqueak is a dual CD4046 stereo device with 14 metal terminals that creates all sorts of chaotic bleeps, crackles, blurps and screeches.

This circuit by Mroztronium started as a tribute to Michel Waisvisz and Geert Hamelberg Cracklebox: a box with metal contacts on top, which generate various unusual sounds and tones when pressed by the performer’s fingers. The human body becomes a part of the circuit and determines the range of sounds possible, thus different people–or the same person at different times–can generate different results.

You’ll find the schematics here and more info in this thread.