The Theremuino is an infra-red theremin. It uses an Arduino microcontroller programmed with a modified version of the Audiuno grain synth.
The performance Theremuino has an infra-red sensor for pitch, and controls for grain delays, speed and volume. It has two modes - polite and rude - which respectively sound melodic and rhythmic/noisy. It's built into an Electro-Harmonix guitar effects pedal box.
Various versions of the Theremuino have now been built, including a simplified one for inclusion in the Circus Kinetica bar for Secret Garden Party 2010, a version housed in stacked perspex, and a spherical 'Energy Ball' version.
Build your own: download the guide, case templates, circuit diagram and the code.
Audio clip: Mike Blow on Theremuino, Alex Allmont on FX pedals