The TrampoLine is an experimental music artwork that is controlled by an Arduino. It has a very interesting control scheme; here is how the creators describe it.
The structure is built around a control handle, which is suspended by 8 flexible sensors. These can be plucked to produce sounds, whilst the bowl itself can be rotated through varying degrees to adjust the pitches of the constituent tones. Each sensor can be controlled separately, or through the movements of the bowl. The rotational position of the bowl also controls parameters of various temporal, spatial and spectral effects.
The TrampoLine- Link