This happened last Friday. ZDnet ran a story on San Francisco's efforts. And here's a write-up on another local temporary park.
FOR IMMEDIATE RELEASE
ACTIVISTS PLAN INTERNATIONAL PARKING DAY ACTION IN PILSEN
Residents to call attention to threatened community garden this Friday
Pilsen, Chicago: in conjunction with international Parking Day, Chicago activists, artists, and local residents will transform parking spaces into gardens in the Pilsen neighborhood.
The action is to take place in the 1900 block of S. Halsted street, from 6 P.M. to 8 P.M. on Friday September 21 2007.
The site was chosen to call attention to a garden space which was deeded to the community by former alderman Ambrosio Medrano, which garden stewards charge was innapropriately sold to Pilsen property mogul John Podmajersky Jr . by current Alderman Daniel Solis. Neighbors and participants in the care of the Cesar Chavez Community Garden, located at 19th and Canalport, were shocked earlier this summer
to find workers cutting down trees on the site, reportedly to create a parking lot for a nearby condominium development. Residents of east Pilsen have organized to fight for continued access to the garden, and will be on hand Friday to help raise awareness of the struggle.
Members of Chicago's growing carfreedom movement saw an opportunity to partner with proponents of the fight to save Jardin Cesar Chavez by targeting Pilsen and Podmajersky with this Friday's action. Payton Chung, a 26 year old urban planner, explains, "Podmajersky and Solis want to replace a garden with parking, so we're going to replace parking with a garden!"
According to the parkingday.org website, PARK(ing) Day challenges people to rethink the way streets are used and reinforces the need for urban open space. Pioneered by San Francisco arts collective Rebar in 2005, PARK(ing) Day 2007 is organized by Rebar and San Francisco nonprofit Public Architecture in association with The Trust for Public Land, which is coordinating a parallel national effort.
Public participation in Friday's action is sought, and participants are encouraged to add their own touches to the installation--additional plants, garden furniture, tiki lights, and outdoor decorations such as trellises and fencing are welcome.