There are 4 tools in the arsenal of wingnut arguing which are really rather hilarious. Let's call them the War on Metaphor, the War on Analogy, Pick the Definition, and the Obsession with Irrelevant Context.
Big Media Matt has been documenting instances of the War on Metaphor, whereby conservatives pretend people who were clearly speaking metaphorically were speaking literally, and criticize them based on that. Andrew Sullivan's been excelling at this one lately.
The War on Analogy, which is one of my favorites, is when conservatives pick apart an analogy by bringing in utterly irrelevent details. For example, if I write "Iraq is, in many ways, like Vietnam," a graduate of the wingnut debating school will respond with "You're wrong! Iraq is in the Middle East!" Or, if one points out to Andrew Sullivan the similarity between Jayson Blair and certain journalistic lapses under his own watch, he could respond with "They're nothing alike! Jayson Blair is lefthanded!" I think Jay Caruso is current champion of this technique.
Pick the Definition works both ways - to cover your ass when you say something stupid and to attack your opponents. Often words mean many things. There are things called dictionaries which list these multiple meanings. So, you can use an alternative definition to claim an opponent meant something other than what is clearly obvious, or you can claim you meant something other than what was clearly obvious (such as Don Strangefeld's musings on the word "slog," which to his credit was admittedly somewhat tongue-in-cheek). This one is so widespread I'm not sure we can pick a winner.
And, finally, we have the Obsession with Irrelevant Context. That's when we get to claim that people were "quoted out of context," when the missing context is completely irrelevant. I'd say Mick the Hack probably wins this one hands down, though self-proclaimed Krugman stalker, and my good friend, Don Luskin is providing some pretty tough competition. Another version of this is the Chewbacca Defense - which is to throw so many irrelevant details into the discussion that is ceases to make any sense.
