I made this map here using a combination of Google maps, and spreadsheets of data. The function of the map is to display the location of old oak trees. Each tree has some data about it, which came from the spreadsheets.  I had changed the style of the map as to give a more nature feel, as the default was a road map.
This is an example of a web mash up, where information from different sources have been combined to produce a new from of information.