I came up with a game a long time ago, when I was bored and working in Canberra. Thinking about how isolated it was, I wonder sometimes why someone else did not come up with the game sooner. I called it the blog photo game.
Anyway, it appears that Google have come out with a far better version: Ingress.
If you have the opportunity to play this game, I highly suggest it. It turns your Android phone into a "scanner" and then you take photos, and check-in to locations around your city, or your country. At the bare essence of the game, you are now employed by Google to make sure their "geo-data" in your city is accurate. It also allows for the creation of other applications like Field Trip.
My apologies to the Apple iPhone faithful. The game is solely for Android appliances. While you may be happy in the fact that you are not an unpaid employee of Google, you are missing out on the fun of this game. Apparently an Apple version is due out soon.