If you can't wait for the start of today's Monopoly on Google Maps game why not warm up with a game of Twaikemon. This Google Maps and Twitter mashup lets you play Pokemon on Google Maps.
To play the game you need to log-in with a Twitter account and then choose your Twaikemon. Once you have a character you are taken to a Google Map with a number of opponents in the form of oval map markers. When you click on a marker you can then choose whether to fight the opponent or not. Fight and win and your character level increases.
This is just an alpha version of the game. Hopefully there will be some further developments. It would be nice, for example, if you could play against other people on the map.