Started by San Francisco art collective Rebar in 2005, Park(ing) day celebrations have spread throughout the globe. This year, the day was observed on September 18th. The (brilliant) idea is to create temporary green space out of parking spaces and stimulate conversation regarding our urban environment and the predominant roll of the car in our cities. (I can imagine some of the "conversations" between participants and drivers looking for a parking space!) I'm all for more green... anywhere.