I have just discovered this wonderful tool that is Google Earth. It is a simulation of the earth with satelite photos that allow you to rotate the globe, zoom on any city, and even have a GPS function with the road network and names in Western countries (but not Japan). Some major cities have so detailed photos that we can even see the cars and identify houses. Some US cities like NY or LA have an option to superimpose 3D buildings on the picture too !

All one could wish for is that all the world could be seen with the same details as those cities. Will come in the future I guess.