[dm2]

It might be a challenge but there's no need to completely dismiss the possibility.

Here is a $5 keychain that can record for 1.5 hours. http://www.amazon.com/808-Car-Chain-Camera-Recorder/dp/B0084...

I'm sure Google and the countless engineers and scientists working on advanced battery technology could make something work for a reasonably long amount of time.

And there's no reason that you couldn't put a laptop size battery in a bookbag with a cord to the glasses and have an all day charge. Either 3 hrs without the optional extra battery or 24 hrs with the 3 lbs bookbag battery, that doesn't sound so bad to me, at least until we create better batteries.