You look at the picture and the initial image on the video, and it looks like a harpsichord with the keys arranged on a cylinder.

... but then you hear the sound and as it so happens, it's actually a bowed string instrument.  It's one of those things that you don't really think about, but it's just a clever little creation, and a variation on the old hurdy-gurdy, but with a lot more range.  The idea is that the \"bow\" is a spinning wheel with a rosined wrapping on the perimeter. The key action simply moves its corresponding string so that it comes in contact with the wheel.  One pedal moves dampers into place to create staccato decays, and the other pedal controls the speed of the wheel to control dynamics.

Insanely expensive, but one can't help but admire the idea.