Asteroids barreled towards Earth from every direction, and my only defense was my eyes. I looked at one asteroid. I looked at another. Boom. Boom. Lasers from Earth had blown them into smithereens. And I didn’t lift a finger.

At CES 2014, a dozen or more companies are vying to track your arms, legs, and even your eyeballs. This demo was from Tobii, an eye-tracking technology company from Stockholm that wants to change the way we read, drive, and game. The company makes Kinect-like sensors, which each have two or three cameras and sit below your laptop’s screen. After two minutes of calibration (which involved staring at several dots as they darted around), I could pinpoint any spot on the screen with my eyes.

Tobii’s “Eye Asteroids” demo was a blast, and was easier to control with my eyes than with an analog stick. Navigating Windows 8 with my eyes, on the other hand, wasn’t as much fun. In order to select an app, I needed to not only look at an app, but then press a keyboard button with my hand. I quickly learned that eye tracking doesn’t solve everything. In fact, the dozens of eye- and gesture-tracking companies at CES seem to be creating more problems than they’re solving.

But a few get it right. Now please, keep your hands and feet inside the car.