Wired reported yesterday that many entities are changing Wikipedia entries to stamp out criticism, including touchscreen voting machine manufacturer Diebold, the CIA, political campaigns and, according to tech bloggers, Fox News . Through a search tool called the Wikiscanner, users can trace anonymous editors to the IP addresses of the computers they use. The tech blog O'Reilly, for instance, used the scanner to discover that someone at a Fox News IP modified the entry for Al Franken to delete a quote from Franken that the 2003 lawsuit against the Minnesotan by the news outlet was "literally laughed out of court" and that the judge's ruling that the suit was "wholly without merit" was "a good characterization of Fox News itself." (Here's a more complete list of changes made by Fox.) No news yet on what the scanner revealed about, say, changes made by users at New York Times' IPs.
Update: Someone with a BBC IP changed George W. Bush's Wikipedia to call him George Wanker -- not Walker -- Bush... although the edit was made in 2005 and didn't last on the site long.