Originally Posted by
studentff
Whole disk encryption (trucrypt, PGP, whatever) with a real passphrase, and if a US citizen, plan to refuse to give up the password and abandon the laptop to CBP.
They can try as long as they want to crack AES256 (again assuming a good password is used). If the government has the resources needed to actually do that, they're not going to waste them on my laptop.
Just make a hundred or more TrueCrypt volumes on the hard drive using disposable passwords, only one of which has private data contained. Fill up lots of gigabytes with these bogus files. Erase the 99 decoys when you get home. Remember to use 'volumes within volumes' to increase security by several orders of magnitude as well.
This would make your data VERY VERY safe. Even if they take a copy, it would cost millions in IT costs to decrypt and take a VERY VERY long time.
http://www.truecrypt.org/