It is an idea that is both simple and wacky: Taking a metered sparking space and turning it into a small, temporary park. Today is Park(ing) Day, a project that began in 2005 and has now spread to dozens of cities across the United States and in other countries.For New York City’s version of Park(ing) Day, 18 parking spaces around the city have been converted, temporarily, for use by pedestrians and bicyclists. (An additional two parking spaces, in Brooklyn, will become mini-parks on Saturday.)This morning, on the east side of Columbus Avenue, between 87th and 88th Streets, staff members from the office of Councilwoman Gale A. Brewer claimed on the parking spaces, laying down grass and then setting up a large beach umbrella, a green table, a wooden bench and a beach recliner. A sign pronounced the creation of "New Columbus Park." Passers-by were offered lemonade and coffee and urged to sit down."I think people were stunned," said Peter Goldwasser, the policy and communications director for Ms. Brewer. "A lot of people stopped, stared, read, picked up literature. It’s a visually incongruous thing that gets people thinking about options for the street and how to create an environmentally sustainable and greener city."A New York Times video by Matthew Orr looks at one of the mini-parks, in Times Square.Transportation Alternatives, an advocacy group for pedestrians and bicyclists, helped organize the New York City Park(ing) Day and coordinated the use of 20 different parking spaces around the city. The organization said that the various spaces included a "vest pocket park" near the Museum of Modern Art; sod and street furniture on a parking space near Pennsylvania Station; a "tribal village" near Lincoln Center, designed by the Endless Love Crew, an artists’ collective, and Chashama, a nonprofit arts organization; an exhibition by the Lower East Side Girls Club on "New York B.C.: Life Before Cars"; and street amenities installed by the Park Slope Neighbors.The Open Planning Project has published a Web site with a full list of Park(ing) Day events in New York City. Streetsblog has been actively blogging the event, noting that squatters occupied parking spaces in Oklahoma City in 1935 and in Oxford, England, in 2003.As the central Park(ing) Day Web site explains, the program’s goal is to "reprogram the street and increase public open space" by creatively turning parking spaces into patches of parkland, with a bit of greenery, seating and shade. The project is organized by Rebar, an art collective based in San Francisco; Public Architecture, a San Francisco nonprofit group dedicated to public spaces; and the Trust for Public Land, a national land conservation organization. The trust is coordinating the national event this year.City officials evidently gave permission, in the form of "miscellaneous street use" permits, for the Manhattan parking spaces to be claimed. "They did give us approval, at about 5:30 last night," said David Vandenberg, the director of development and Upper West Side programs for Transportation Alternatives.The lawfulness of using the spaces outside of Manhattan as temporary parks is a grayer area. Transportation Alternatives believes the Park(ing) Day events are covered under the First Amendment; the city has essentially been looking the other way.All of the 18 parking spaces converted to parks today will be returned to their regular use by tonight. Saturday, two spaces in Brooklyn - one in Fort Greene, the other in Park Slope - will have a Park(ing) Day of their own.