Google GLASS is a pretty interesting device. But it is not cheap at all. You could always try to make your own though. Tony’s $60 Bluetooth Head Mounted Display project might give you a few ideas. This is a Google GLASS like device that is compatible with both Linux and Android. It will display information from your smartphone. The device has a 0.96″ display that is controlled by an Arduino nano board. These glasses are portable and foldable. The whole project costs about $60. How about that? You can follow the project on Hackaday.