A team led by Jefferson Han has been conducting research on multi-touch sensing technology, i.e. touch-screen interactivity that goes far beyond what you see at the drive-up ATM machine. Apparently Apple owns the patent on the work, and as this video shows, the potential for the technology is huge. Han writes, "The sensing technology is force-sensing, and provides unprecedented resolution and scalability, allowing us to create sophisticated multi-point widgets for applications large enough to accomodate both hands and multiple users." Translation: by "grabbing" images on a screen you can scale them, scroll, draw graphs, set levels like a sound engineer or DJ would, etc.
Also: See the Dialog Table, an interactive tool at the Walker that uses gesture-recognition technology for accessing info on contemporary art.