"WikiScanner is a relatively new site that will track the edits made on Wikipedia.
The purpose of this service is to see who’s behind edits made, and how these actions generally lend themselves towards the self-interested corporations hoping to promote and protect brand identities. "
mashable.com WikiScanner Identifies Editors on Wikipedia
"List anonymous Wikipedia edits from interesting organizations" by Virgil Griffith
Example: Sony anonymous wikipedia edits