Passware Kit decrypts hard disks encrypted with BitLocker or TrueCrypt in a matter of minutes if the target computer is running. Now Passware Kit is capable of this instant decryption even for powered-off computers by analyzing a hibernation file (hiberfil.sys).

The software instantly extracts BitLocker and TrueCrypt encryption keys from a hiberfil.sys file, which is created automatically when a system hibernates. This means that if the target computer with a mounted BitLocker or TrueCrypt hard disk has hibernated at least once, Passware Kit will instantly decrypt the hard disk even if the target computer is no longer running.
http://bit.ly/pw-55