This is pretty cool. A co-worker of mine showed me something similar recently.
On a somewhat related note, I’ve always thought it would be cool to study how much time is wasted moving your hand from your keyboard to your mouse when using your computer. Having multiple screens at work, it seems really inefficient dragging my mouse all over the place. I mean, I do use a lot of hotkeys and stuff, but still. It would be cool if there was some sort of sensor on my glasses that would sense my eye movements and move the cursor on the screen.