Are you ready to explore some nice maps? We are going to navigate through a great bunch of spatial data, OpenStreetMap.
Open your browser and go to http://www.openstreetmap.org.
The website offers you a small scale map centered on your actual location, as derived from browser information.
Center your map on London, UK and zoom in with the tool shown on the left-hand side. You can see that many more road types and locations are now shown in the map:
Now enter the Piccadilly Circus, London, UK address in the Search textbox on the left and press the Go button. A list of results matching your search is presented on the left side of the map. Pick the first item:
The map is now at a great scale (look at the scalebar on the bottom-left angle) and the symbols are changed to show you greater detailed information about roads and locations. You can find street names, directions for car traffic, buildings' footprint, and icons for points of interest. The general look and feel resembles a printed city map you can pick up at tourist offices.
Note
OpenStreetMap does not require you to register for browsing or exporting the data. Anyway, if you are interested in maps and open source data, you may consider getting involved in the project. OSM is a collaborative project to create a free editable map of the world, currently involving over half a million users all around the world. You may add data or find errors on locations you know well.