On April 22, the 40th anniversary of Earth Day, Christie's International will become the art world's first major powerhouse to commodify going green. "A Bid to Save The Earth," its inaugural Green Auction, will be held at Rockefeller Plaza and will benefit four select charities: Conservation International, Oceana, Natural Resources Defense Council, and the Central Park Conservancy. The evening will welcome 600 guests, hosted by a star-studded line up that includes Cameron Diaz, Leonardo DiCaprio, Francois-Henri Pinault, and Salma Hayek, as well as collectors Susan and David Rockefeller, Jr. and Anna and Graydon Carter. During the week leading up to the sale, NBC Universal, the event's official media sponsor, will air environmentally themed coverage to raise "green awareness."

If your last "celebrity experience" was merely gawking at Jay Z while he shopped Art Basel Miami, look no further — along with eco-travel packages, jewelry, cooking classes with Alice Waters of Chez Panisse, bidders can also compete for a chance to spend the day with Hollywood's elite, touring around the set of Californication with David Duchovny (estimated value $5,000) or enjoying a private screening of Avatar with Sigourney Weaver (sounds much better than viewing in 3-D). Artworks by Keith Tyson, Maya Lin, Subodh Gupta, and Olafur Eliasson will also be available for bidding, with a silent auction of additional luxury items running from April 8 – May 6 at Charitybuzz.com. If none of the above are inspiring, participants are encouraged to donate, volunteer, educate, or green their routine online.

The greening of the auction itself, for which Christie's will also waive their usual commissions and buyers premiums, will come by way of producing e-catalogues in place of print. All event marketing will also be done electronically. Further, guests who are traveling to New York are encouraged to purchase carbon offsets for their trip through NativeEnergy. It is yet to be determined whether these changes will be implemented for future events — which is how a real difference could be felt — or just the one-off sale.

But why did Christie's decide to go eco-conscious now? In their words: "Environmental concerns are increasingly important to our clients, their families, and our staff, and we share their concerns." So rather than twiddle their thumbs while collectors hold onto their good artwork as the recession lags on, Christie's has found a creative way to keep the buying momentum going — all for a good cause.