New York's Park Avenue closed to car traffic for the summer on Saturday mornings
Here's a piece by NY Times' bicycling photographer Bill Cunningham (who claims he's had 27 bikes stolen over his career with the Times...).
http://video.nytimes.com/video/2010/...ref=multimedia
Is closing streets on the weekend getting a popular thing to do? From the look of this video, a lot of people had a great time.