Today is international Park(ing) Day, which is a grassroots event in which people buy a parking space for a day (by feeding the meter), and then use it as a miniature "park," for people, instead of a place for cars. Sometimes city governments get in on the action and make it official. There are probably hundreds of both official and non-official events going on all over today.
Is it going on where you live? If so, post some pics.
Here are some pictures from a city-sponsored version in Arlington, VA, taken at lunch today: