[mey]

Consider Google Glass a HUD. (Not sure if that is their desired term but it's the closest commonly known example). Glass is not attempting to tackle AR at the moment.

See this for more background on why it won't be anytime soon. http://blogs.valvesoftware.com/abrash/why-you-wont-see-hard-...

See these for even more background

  https://en.wikipedia.org/wiki/Optical_head-mounted_display
  https://en.wikipedia.org/wiki/Head-up_display

[dm2]

The prototype hardware running Glass is not ideal for AR but it appears to be technically possible and obviously very useful.

http://www.slashgear.com/google-glass-augmented-reality-gets...

http://www.popsci.com/technology/article/2012-02/video-nano-...

Below would be the goal. The story is slightly cynical but the AR games and even pictures on the walls are very cool. http://www.youtube.com/watch?v=GJKwHAvR4uI