Reactable : Future Wheels Of Steel?
Reactable is an electronic instrument that uses a future-thinking tabletop interface. Watch how the user puts objects on the table and then positions them to change beats and sounds.
The description over on YouTube reads:
The reactable, is a multi-user electronic music instrument with a tabletop tangible user interface. Several simultaneous performers share complete control over the instrument by moving physical objects on a luminous table surface. By moving and relating these objects, representing components of a classic modular synthesizer, users can create complex and dynamic sonic topologies, with generators, filters and modulators, in a kind of tangible modular synthesizer or graspable flow-controlled programming language.