CDM points out this very sweet beat manipulator interface by Luca De Rosso. The project, better known as OTTO, makes use of an Arduino board, MAX/MSP software, and an array of LEDs + switches to create a very intuitive and approachable experience for musicians. –
OTTO is a new musical instrument for beat-slicing, the technique that allows to create complex and variegated rhythm sections by using just one rhythmic audio sample, cutting it into little pieces and rearranging them in time. OTTO provides a hardware solution with a strong visual feedback, to allow the musician to control the audio sample as if it was in his hands.
Circular sequencer devices really seem like a step in the right direction for audio hardware – much more intuitive for loops. More demo vids and source documentation/downloads available on the OTTO site