Thematic Google Map Creator
University College London (UCL) has been very busy and using their resources have made an excellent thematic mapping package for overlaying on google maps.
The Google Map Creator is a freeware application designed to make thematic mapping using Google Maps simpler. The application takes a shapefile containing geographic areas linked with attributes and automatically generates a working Google Maps website from the data. It does this by pre-creating all the necessary files and saving them into a directory. Publishing the map on the web is then just a matter of copying files onto a web server, allowing Google Maps to be used with the majority of ISPs, including Google Pages.
"How It Works?
The main problem with creating Google Maps sites in this way is that the number of tiles can be very large. The application manages this problem by allowing the user to control the maximum level of zoom and the extents of the geographic area. For example, with a map of worldwide Gross Domestic Product by country, there is no point in zooming in beyond the point where one country fills the whole screen, so the maximum level of zoom is limited and the number of tiles kept within a manageable level. In this example, six zoom levels are adequate for the data, resulting in 962 files occupying 5MB on the disk. At the other end of the scale is data from a GPS tracked carbon monoxide sensor used within a 1KM grid square in London. In this case, the maximum zoom level is used to show the 5 metre data grid, but only 71 files (less than 1MB) were created as the geographic area is so limited. "
Download available from the UCL website
Excellent Work UCL - Mapperz