Give a Minute
Give a Minute has used the Google Maps API to create a very interesting campaign. The Give a Minute campaign is encouraging people to post ideas about how they can improve their cities.
The site contains four customised Google Maps, one each for Chicago, Memphis, New York and San Jose. Each map replaces the Google Map tiles with a custom image of the city. The latest ideas submitted to the site are then overlaid on the image in the form of post-it notes.
Using the usual Google Maps navigation controls you can zoom in and read any of the submitted ideas. You can also order the ideas by 'most recent' and 'most shared'.