The video: Sweden's Tobii Technology and laptop-maker Lenovo are offering a glimpse of the future: A computer controlled by eye movements rather than a mouse or touchscreen. The prototype, unveiled this week at a trade show in Hanover, Germany, lets users control a cursor, scroll through text, zoom in on pictures, and even play video games by tracking where they're looking. (See a video below.) The system shines two invisible infrared lights into your eyes, and uses a hidden camera to spot direction-setting glints in your retinas. Tobii says the system isn't intended to replace trackpads, but merely to complement them.

The reaction: Many tech companies believe motion controls like those used with the Xbox Kinect are the future, says Chris Ziegler at Engadget. "But it's an awful lot of work to wave your hands around every time you want to change windows, isn't it?" This eye-tracking system, on the other hand, "works extraordinarily well." Yeah, this sounds "awesome," says Jared Newman at PCWorld, "but don't expect to control your PC with furtive glances anytime soon." Only 20 prototypes have been produced so far and the system won't be commercially available for a couple of years. Watch a video about the eye-tracking technology: