Google Maps 5.0 for Android - contains awesomesauce
Holy moly. Not only does the new mobile version of Google Maps render your surroundings in 3D, but it syncs with your smartphone's compass to change the orientation of the map as you turn. Google are also promising improved offline use of maps too, and lots of other bells and whistles besides.
It's only available for Android users at the moment, so feel free to piss on the chips of iPhone users everywhere.