Have you heard about this thing?
It's a database of anonymous edits to Wikipedia (where the IP address is
recorded) which links them to the organisation those IP addresses are
registered to belong to. So you can search for an organisation and get
a list of edits that were made from a computer on their network, i.e.
almost certainly by someone who works for them (though there's always
the slim possibility it was done by a guest allowed to use their
computers, or a hacker who broke into their network).
Lots of interesting things have emerged since this program was made
available about two weeks ago. For example, someone from Diebold
removing several paragraphs about the flaws in their voting machines,
and Exxon whitewashing the harm to wildlife caused by the Valdez oil
spill. There's a few health-related things, including Monsanto spinning
criticism of their Roundup herbicide.
Wired is collecting a list here, where people can vote on 'the most
shameful Wikipedia spin jobs':
I'm sure you'll have fun with it! ;-)