I think this is going to be really neat: you walk around the streets of San Francisco, for example, with your Android powered phone, en route to your destination 20 blocks away.
You whip out your phone, go to Google Maps, pull up the StreetView (remember this?), which zeroes in on your location using a built-in GPS, and then changes as you move the phone around using the built-in compass.
You then virtually walk the city, looking around, without actually moving an inch (looking for the closest ATM, restaurant, etc, hint-hint?).
Without further ado, let's have a look at this video from Google's I/O Conference for a demonstration?
This video is really the 2nd part in a series but it was the most interesting one. Part 1 follows for the curious:
Edit: I found a nice related video by G4TV. Here it is: