Wikipedia is upgrading their servers and are donating the cast-offs to non-profits:
http://blog.wikimedia.org/2011/06/13/server-decommission-donations/Wikimedia Foundation has been upgrading and adding new servers to keep up with traffic demand and capacity growth as we always do. Recently, we replaced some of our older servers with faster, higher capacity and more energy efficient servers. These older servers are now decommissioned and will be donated away. Do note that they are over 3+ years old and are out of warranty. While we may have placed a lot of demand on them over the years, they are in fine working condition.
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If you are interested, please provide the following information in your email to us:
Registered non-profit name and information.
Your contact information, including email address, phone number, and relationship with requesting non-profit.
Information on the non-profit, their charter, mission and goals.
Shipping address information for a FedEx Ground delivery (i.e., the shipment destination)*
How the servers will be used. (We like to know and share with folks!)
* At this time we regret that we are only able to ship servers to USA based non-profits. This is due to the cost of shipping and the various exportation laws and taxes that result from shipping internationally.
(read more at the link)