Maps.a9 is a new map service from google that allows the user to see pictures of the street selected on the two-dimenstional map of the city. The pictures were entered by vans equipped with powerful GPS receivers so that each picture was correctly taken.
This was one of the application we were sketching and thinking about many times during these two last years. They did it. However in our vision the power rester to the people. We were thinking about a more collaborative mechanisms to provide the source data.
(thanks Antonio for the link)