Noticings describes itself as "the game of noticing the world around you."
You play Noticings by uploading to Flickr geo-tagged photos of interesting things (not including people or other very transient things) you've noticed when you're out and about.
You get points for spotting the first instance of something in a neighborhood or by a sustained noticing of some particular spot or thing over time.
You can find rules of the game, how-to instructions and lots of photos of odd things here.
As of this writing, no one in Athens, Georgia was playing Noticings.
Via Digital Urban.
Image credit: Screen shot of Noticings banner.