The SilverStripe open source CMS lets you use Google Maps to GET your website forum members to mark their location and build up a world map of all members.
SilverStripe Google Maps Forum
Original Article
Google Summer of Code Fruit #7: Google Maps - SilverStripe - Creators of the Open Source CMS & Framework
Google Summer of Code Fruit #7: Google Maps - SilverStripe - Creators of the Open Source CMS & Framework