http://www.freecycle.org/

"The Worldwide (!) Freecycle Network is open to all cities and to all individuals who want to "recycle" that special something rather than throw it away. Whether it's a chair, a fax machine, piano or an old door, feel free to post it. Or maybe you're looking to acquire something yourself! One constraint: everything posted must be free. Just pick your city on the left and it'll link you to their website, or sign up with that city directly by e-mail below. And, as Abe Lincoln once said, "Think globally, recycle locally."