This is a must have for augmented reality to kick off. The glasses you wear need to know where you are looking. So if you look at a restaurant across the road, and ask “menu”, then you can be shown the list of food as an overlay.

While all VR glasses are clunky, they will certainly get smaller, just like cellphones have.

The Fove is a VR headset with eye tracking built in, accurate to 1/5th of a degree, and it can track your head’s position as well:

The other cool use, is that when you are represented by an avatar, your eyes can reflect where you are looking. This will be a powerful addition to making avatars seem real, or at least an analog of real.