This project scares the hell out of me. This is going to cause eye problems and distract people and cause injury and accidents.
http://www.amazon.com/Third-Eye-Round-Helmet-Mirror/dp/B0012...
I have to stop looking forward to use it, for just a small part of a second, because of different focal distance, different angle of my eyes, limits in the brain part that focus the attention, etc.
It actually helps me avoid accidents.
I don't see how Google Glasses would be much different to that mirror. I would love to use them for GPS or other related info. Focal distance in tiny screens is either a solved problem, or one being solved by smart people right now.