[yaeger]

Not necessary to do harm to your data.

What you want is truecrypt with a shadow partition. See, forensics can tell if your laptop drive has an encrypted partition. But they can't tell how many. So, set up a dummy encrypted partition with user/pass and your normally used partition with user/pass.

Depending on which user/pass you enter, truecrypt will decrypt the appropriate partition. The government can snoop all they want on your dummy partition. They will find nothing. When they ask why you encrypted it, you tell them because you always protect your things. You also lock your house when you leave etc. Of course you should have some things on your dummy partition that make it look like it is actually being used. If you just have a freshly installed OS with no sign of usage, that might get noticed.