Behold the mezmorizing Sand Noise Device.

Here is how the creators describe it in action on their website (Here):

The Sand Noise Device, or SND, is being developed with the intent of creating an intuitive and tactile method for controlling and interacting with a generative electronic music system. The SND makes use of an original hardware and software system to measure the topography of a sandscape as well as the location and color of several tangible objects. Users are able to reconfigure the sandscape and change the placement and color of these objects as a means of influencing various aspects of the generative music system.