Fricosu keys
TrueCrypt and LUKS need a Fricosu key. This is a second key, created when the encrypted volume is initialized which, when entered under duress in Colorado, would cause the system to silently and permanently forget the real decryption key.
This would be good for journalists traveling to Brazil and getting nabbed by the Bobbies, but it wouldn't do a shag bit of good if the drive has already been imaged.
Well, it's better than nothing.