A tangible CAD interface.
To learn about how to build the Cubecube hardware that accompanies this software, check out the Cubecube instructable. From our instructable's description:
Cubecube—an open-source hardware project—is a tangible, tactile interface for CAD (computer-aided drafting.) As open source design platforms continue to emerge, there is an opportunity to explore new possibilities in how we create. The Cubecube project aims to investigate the question: If there were a platform for using your hands to build three-dimensional computer models, what might it look like?
We also have a website where you can track this project as it progresses.