Rectable looks so damn futuristic that I had a hard time believing it was a concept of our time. The reactable hardware is based on a translucent round table.
A video camera situated beneath it analyzes the table surface continuously, tracking the nature, position and orientation of the objects that are distributed on its surface. These objects represent the components of a classic modular synthesizer.
The objects are passive without any sensors or actuators, users interact by moving them, changing their position, their orientation or their faces (in the case of volumetric objects).
Actions control the topological structure and parameters of the sound synthesizer directly and in real time. A projector, also from underneath the table, draws dynamic animations on its surface that provides a visual feedback of the state, the activity and the main characteristics of the sounds produced by the audio synthesizer. Enjoy the show.
Update: Rectable is now also available as a smartphone application for Apple iOS and Google Android devices. The application is not free but still highly popular in both stores. The apps provide you with a similar experience even though it is limited in comparison to using a physical reactable setup where you create sound by placing elements on the table. Here, you place virtual elements on the same table structure.
The reactable website offers downloads and sound track videos from artists who are using the table to create music. Here you find a couple of interesting and great sounding tracks. While you are free to watch and listen to the music videos posted on the side, you can't download all tracks to your PC as at least some are limited to users of the mobile app. The community is however an interesting starting point to explore what the tablet has to offer.