This is a pretty neat invention- http://www.games4rehab.org/Sheryl/videos/130

The team at Waterloo Labs have developed a method of playing video games with eye movement.  Basically, as they explain in their video, the eyeball is polarized with more negative charge near the back and more positive charge near the front of the eye.  With reference electrodes and a ground, they can determine the position of the eyeball as it moves left, right, up and down.  The setup looks kinda quirky but the function is nice. The only barrier I see to using it in the game, is that you need to reposition your eye ball back to the center to look at the game. One compensation used by a player on the video is to turn his head left and right, up and down to position his eyeball in a "relative" left or right position.  This makes more sense to me.  AND...this brings up another potential rehabilitation tool.  For individuals with Vestibular Optic reflex (VOR) issues or other vestibular impairments, perhaps playing video games by moving your head while keeping your eyes glued to the screen could help with VOR training.  

Thoughts?