Over a year ago, I discussed a magistrate's opinion in a case captioned in re Boucher, which held that providing a PGP passphrase or otherwise decrypting an encrypted PGP volume to aid in a law enforcement investigation against one's self violated the Fifth Amendment. I'm amazed to discover that there is even a Wikipedia page for this case (here).
The magistrate's decision has been reversed by the U.S. Judge for the District of Vermont, directing defendant to produce the drive in an unencrypted form.
Because I need not attempt to duplicate Professor Orin Kerr's apt coverage of this latest development, allow me to point you to his commentary here.
Defendant's attorney, Jim Budreau, filed an interlocutory appeal to the Second Circuit.