In no particular order and certainly not an exclusive list, perhaps...

John Kerry
George W. Bush
Tony Blair
Saddam Hussein
John Edwards
Ronald Reagan (R.I.P.)
The Dalai Lama
Bill Clinton
Ralph Nader
The Pope
Donald Rumsfeld
Ariel Sharon
Yasser Arafat
Vicars (in general)
Dick Cheney
Halliburton Inc.
Michael Moore
Millard Fillmore
John Howard
Michael Howard (no relation)
The Rev. Ian Paisley
Monica Lewinsky
Jerry Adams
Nigerian 419 scammers
The International Accordeon, Banjo, Bodhran and Saw Manufacturers Association
Gurus (of various persuasions)
Mike Harding
Kim Howells
Various government agencies with initials, in assorted countries
Eminem
Clear Channel
Cletus
Valéry Giscard d'Estaing
Karl Marx
Adam Smith
Sonny Bono
Bugs Bunny (he's definitely at the root of it all, I'm sure of that)

I strongly suspect all these people are posting, or have posted, potentially annoying and provocative material posing as perfectly innocent Guests...

Peace

moo