At times, I have been guilty of running up too close to the line myself. Others have obviously crossed it.
So, let's remember, attack the argument not the person making it. Personal insults don't do anything to advance the discussion. And name-calling is, after all, middle-school stuff.
UPDATE: That doesn't mean I won't link to sites that promote this type of middle-school stuff. Like this one. But WE'RE better than that!