Enkin is a new hand-held navigation concept being developed by two German 'computational visualists'. It combines GPS, orientation sensors, and what looks like Google Maps and Google Earth.
In essence Enkin seems to take placemarks that you have created in Google Maps and overlays them on top of a live video feed of the same location.
It looks absolutely amazing. Just watch the video to see what I mean.
Enkin from Enkin on Vimeo
I want the first pair of sunglasses these guys produce with a built in monitor. Augmented reality here we come.
You can learn more about the technical details of this at Enkin.net.