D-Touch.org has released the D-Touch Drum Machine, a drum machine with a tangible user interface.
It is controlled by placing and arranging physical objects on an A4 piece of paper, which we call the interactive area.
The interactive area is arranged in 11 rows, each row corresponds to a different sound, as indicated by the text labels. The horizontal position of the blocks on the interactive area determines the timing of the sound trigger within the loop.
You can find detailed instructions on how to assemble and setup your own D-Touch Drum Machine here.