Could not believe it when I first heard about it. Someone ported the board game Risk to Google maps. When you start the game you see a world map and some lines drawn that are the borders. They look exactly like the risk game layout.
There are no computer players for now, so its only really playable in hot seat mode, unless you have multiple personalities, then that might be the perfect game for you. Take a look at this astonishing Google maps game and tell me what you think of it.

Weekend Fun JRisk
Google Maps Downloader Offline Maps
Google Maps Downloader And Joiner
Bing Maps 3D