[lambda]

[TrueCrypt](http://www.truecrypt.org/) or [dm-crypt](https://en.wikipedia.org/wiki/Dm-crypt) are both open source (technically, TrueCrypt has source available but doesn't meet the definition of an open-source license, though there's some debate on that point), and thus publicly auditable.

Also, I'm less worried about FDE being vulnerable to Border Patrol than about, say, SSL vulnerabilities across the whole network. The plausible deniability, which they would need to use to protect their sources if they found information, is a lot lower if you know you have been stopped and your laptop searched, rather than just tapping all internet traffic so you don't even know when you've been searched. Mac OS X's File Vault 2 and Windows's BitLocker are probably sufficient if if you aren't particularly paranoid about being individually targeted for something big, but I would be more inclined to trust the open solutions.