This could be one of the best yet:

Q The Nixon tapes case, though, presents certain limitations on the President’s assertion of executive privilege, doesn’t it? MR. SNOW: How on earth are you trying to apply the Nixon’s tapes case here? That seems an awful stretch. Q I read it in the paper. It sounded logical when I read it. MR. SNOW: Well, it’s — nice try. Q Thank you.

I guess that’s a better answer than, “Helen told me to ask it.”