LUKS/dmcrypt is an excellent fully open source alternative to Truecrypt.

http://code.google.com/p/cryptsetup/

Exactly; I don't see why people have such a hard-on for TrueCrypt when you get LUKS out of the box on a Debian install. It's a no-brainer.

I can send them to Windows and Mac users. Even non-technical types seem to be able to open transcript volumes.

While blowing my cover a little, here's an anecdote about LUKSfs-encrypted drives:

I was arrested sometime in early 2011 (let out after 7 hours without charges, which was a fun story in itself). In my pocket, they found two USB sticks. one was a Linux Mint LiveUSB. The other USB stick was encrypted via LUKS. The police could have booted of the LiveUSB, and then inserted the second USB to decrypt it. if they had decided to force me to divulge my password, they would have found all sorts of incriminating things to keep me for longer.

However, this did not happen; when inserted in the police's Windows PC's, they merely popped up a "This drive is not formatted. would you like to format it now?" message. Naturally, they clicked "no" and gave me back the stick. I owe a part of my freedom to Microsoft's and my local Police's devotion to the Windows OS.

TL;DR - LUKS not working in Windows OS is a feature, not a bug.

To that I add that I specified that Debian offered LUKS at install; if you're going with whole disk encryption and doing enough in Linux to care about it, you won't care about being able to read that partition in other OSes, especially ones you don't have the source code to.

Anyone had luck compiling this on OSX?

it doesn't support hidden volumes (deniable).

There's another implementation for TrueCrypt these days, tc-play, https://github.com/bwalex/tc-play that looks promising.

DragonflyBSD is impressive and is trying to improve on modern OSes (See HAMMER filesystem). I hope tc-play becomes crossplatform.

I've been using tcplay on Debian for about a year now.

If the NSA has the ability to break into TrueCrypt drives, then they aren't going to tip their hat on the matter, even in the case of child pornographers. They would probably only be willing to let that information out for very high value targets, because in the meantime, people are still using it and they can still get access to it. If people know that the NSA (or whomever) can get into TrueCrypt volumes, then they stop using it.

Do they need to tip their hats, even when dealing with "high value" targets? Once you've found what you're looking for, you could easily find other damning information that could have plausibly come from somewhere else, no?

While possibly true, not every situation will lend itself to easily finding other damning information with a plausible outside source.

Just look at WW2. There were times that the Allies knew things would happen, but couldn't act on them because it would tip their hat to the Germans that there was a leak somewhere (possibly leading them to the knowledge that the Allies had cracked Enigma), and the pay-off wasn't worth the risk.

Oops: s/tip their hat/tip their hand/