OpenStreetMap

I tried out OpenStreetMap the other day after reading the recent article about it on LWN. Amazingly it looks pretty complete for the parts of the UK and US that I looked at. I don't know how much comes from people gathering data by travelling around or by entering data from satellite photos or out-of-copyright maps, but whichever of these it is, it's very impressive.

It is also better than Google Maps in some ways:

• It has more details: it shows footpaths, rivers and streams, wooded areas, and paths across parks. It has outlines of interesting buildings where people have entered data for them.
• I think the default renderer (Mapnik) looks better than the Google Maps equivalent, especially when zoomed out to a level where streets are one pixel thick but still distinguishable. Google Maps gives too much prominence to the major roads -- it renders them thickly, in bright colours, and with large labels, which tends to drown out the details. Mapnik is more subtle. The map just looks more interesting.
• It uses more of the browser window and doesn't waste as much space on sidebars. It's almost a trivial point, but it makes a difference.