Was watching this Oculus Rift vid. The lady had a plumbing problem with her toilet, she contacted a tech over the phone and the tech was able to put a virtual display over the plumbing components and walked her trough the repair. He demonstrated what to do virtually and she was able to copy his actions.
Wow! This is going to be big. Imagine doctors helping out an EMT on the battlefield or a chef walking you through making a chocolate mousse.