Wikipedia Scanner -- the brainchild of CalTech computation and neural-systems graduate student Virgil Griffith -- offers users a searchable database that ties millions of anonymous Wikipedia edits to organizations where those edits apparently originated, by cross-referencing the edits with data on who owns the associated block of internet IP addresses.

Virgil's on Wired. :)

(Update: Slashdotted)

See Who's Editing Wikipedia - Diebold, the CIA, a Campaign