CortoMaltese noted that the U.S. intelligence community has unveiled their own classified wiki
, the Intellipedia. Reuters says "The office of U.S. intelligence czar John Negroponte announced Intellipedia, which allows intelligence analysts and other officials to collaboratively add and edit content on the government's classified Intelink Web much like its more famous namesake on the World Wide Web.
A 'top secret' Intellipedia system, currently available to the 16 agencies that make up the U.S. intelligence community, has grown to more than 28,000 pages and 3,600 registered users since its introduction on April 17. Less restrictive versions exist for 'secret' and 'sensitive but unclassified' material."
For kicks, you can also read about Intellipedia on Wikipedia