Google maps is one of the more interesting technologies released in recent times and some of the applications that have been built on the API are delivering some cool services.

The Google Maps Mania Blog has put together a list of 100 mashups using Google maps.  These range from finding a public toilet or wifi hotspot to measuring the area of a mapped location.

This is a great example of the power of an open platform.  If people had to develop these applications from scratch, or license the API to use Google Maps, they would never exist.  Conversely, by building a platform that other people can develop on, Google increases the value of their product. 

While they don’t charge for use of Maps now, there is an obvious path to geographically relevant advertising.  Google has been mapping search results, particularly businesses to maps and allowing geographic searches for businesses.  The obvious extension is to offer premium positioning on the map to businesses that pay a fee.  Other businesses don’t need to be excluded, but the map reference can be more prominent or contain more information in the summary pointer than non-paid locations.

Definitely check out the list though as there are some interesting ones there.