It looks like $21 million in Intel cash and a few promising prototypes weren't enough to convince manufacturers to build eye-controlled tablets quite yet. Tobii, the company behind the eye-tracking Gaze technology we sampled at last year's CES — and again at CeBIT — has just announced a standalone eye-tracking kit you can add to any existing Windows 8 computer. It's called the Tobii Rex, and it's a stick-like device you mount underneath your screen and attach to a USB port on your PC. The company says you'll use it alongside traditional peripherals like mouse and keyboard, as it's meant to augment rather than replace.

For the short term, though, you probably won't be using a Tobii Rex at all: the company's producing just 5,000 of them for consumers to start at an unspecified price, and selling them to developers at $995 a pop in the meanwhile. At that rate, we certainly hope that the system is more responsive than the prototypes we've tried before. If you're just looking for a touchscreen replacement, Leap Motion might be a promising alternative: the company's already shipped out 10,000 developer units of the Kinect-like system, and is targeting a $70 price point. Still, it's hard not to love the game of Fruit Ninja when you play it with your eyeballs.