Truecrypt has been a trusted name in on-the-fly encryption for ages (v5 arrived in February). What’s new in version 6? Plenty.
One of the biggest advances is support for multiple processors, which provides a boost in the encryption/decryption speed equal to the number of processors/cores in use. Other tweaks have increased the overall speed by as much as 20% in some operations - on top of the parallel processing gains.
And - holy crap - how about being able to run a fully encrypted, hidden OS? Yeah, version 6 can do that, too. There’s even a handy guide on Truecrypt’s website. It’ll also hide volumes, and on Vista and Windows 2008 you can even hide a system volume (not on XP, though).
They’ve really done it right this time. If you don’t have Truecrypt, get it. We’ve all got some data on our PC that deserves a little extra privacy and protection. Mac and Linux versions are also available, so everyone’s invited to the Truecrypt party.