If you’ve done any time in project or staff meetings, you’ll recognize a number of these archetypes (The Talker, The Killer, etc.) as well as some contributed by Jonathan’s readers in the comments.
Personally, I have always been in complete, bewildered awe of The Stealth Lurker:
The Stealth Lurker
You might think this guy is a real lurker, but he isn’t. He’s the one who says nothing for the whole meeting then offers a single quietly stated opinion near the end. Then, no matter what everyone else agreed on, his plan gets implemented. How did it happen? Who knows. This guy has some power you don’t understand. Get to know him.
(Also posted at Knowledge Work.)