Anyway, Special Counsel Fitzgerald, in a filing from Sept 7 (22 page .pdf), opposed Libby's use of a memory expert (I meant to post this last week, but I forgot...)
Team Libby responded on Sept 15 (18 page .pdf).
I will read these later, but there they are.
Also check out Clarice Feldman's piece in the Weekly Standard reviewing the current case against Libby. Ms. Feldman has delivered a comprehensive yet concise defense brief highlighting the many problems with the prosecutor's case; in fact, I will be so bold as to say that this is the best defense of Libby I have seen (and way better than my suggested insanity defense).
That said, I am firmly on both sides of this - clearly, fans of the prosecution will prefer to emphasize a different set of facts. Put briefly, it may well be that Fitzgerald is worried that Libby lied about the involvement of Dick Cheney but indicted on these counts because it was all he thought he could prove and he was hoping for cooperation and a plea deal.
MORE: Frequent commenter Jeff has already picked out two highlights from the filings- contra 'Hubris', Libby did testify that Cheney told him about Ms. Plame in his first FBI interview (that fact was also in Libby's notes). And the filing mentions that TIME reporter Matt Cooper's notes "tend to impeach, rather than corroborate, the claim that Mr. Libby confirmed anything about Mr. Wilson's wife".