SteelSeries has partnered with Tobii Technology to create an eye-tracking peripheral set to come out mid-2014. The device will let gamers use their eyes to control certain aspects of games. The eye-tracking is used in conjunction with mouse and keyboard controls. So for instance you'll use your eyes to aim where your character needs to shoot, and then pull the trigger with your mouse button.
The Tobii EyeX dev kit is available for pre-order from Tobii for $95, and those attending CES this year will be able to try out the new tech.
Interesting idea, but all I care about in this general field is the Oculus Rift. I needs that.