Here's a cool thing that T found -- some folks took a metered parking space in downtown SF and turned it into a little park for the day, complete with grass and a bench.
There are more pictures, along with a map and detailed instructions for constructing your own, on the site. What a neat idea. I wish I'd seen it in person.
This came from a discussion I was having with grue23 the other day. Just curious. I will summarize results later if people are interested. Feel free to invite others to participate.