If it was up to me (and it's not), and I could combine Google Earth with one thing, I would combine it with zombies. Well, that's EXACTLY what upcoming Sony Computer Entertainment title The Last Guy does — it's like they read my brain! Details are scant, but the top-down PS3 game has players use Google Earth to rescue large numbers of people by having them follow you to safe escape zones and avoiding gray matter eating zombies. Sounds like it'll be a PSN game and sounds like it will be totally awesome.
The Last Guy [Official Site]