updated 06:30 pm EST, Fri January 9, 2009
Surf Google Earth
David says that he wrote the application to inspire users to write their own programs. The Javacript was based on an open source program Monster Milktruck, while the Balance Board was based on DarwiinRemote open source decoders for the Wii Remote.
According to the posting, both Earth Surfer (and source code) will available in mid-January on the Google Mac Developer Playground.