Drive Encryption

I'm looking for some freeware drive encryption software. I have found a few apps that encrypt individual files and folders, and I suppose I could just move everything into one folder and encrypt it, but I'd rather just encrypt the entire drive. Any suggestions?

Thanks!

BTW- freeware is not mandatory but is highly preferred, as is DoD or similar encryption standards; I plan on using a minimum of a 15 character alphanumeric password and a different 15+ character alphanumeric key, but I guess this depends on the software; I'm not very familiar with encryption software, but from the little research I've done, I know you need a password to access the encrypted data, and a key which determines the encryption 'pattern' or code, but that might depend on the encryption program.

Oh yeah... WinXP Pro SP2. The drive to be encrypted is a 320gb drive with about 250gb of data on it, but some of the data (maybe 50gb or so) will be shredded before encryption.

 

I've spent the past 10min or so at the TrueCrypt site linked to above, and... W O W ! ! ! I had no idea the complexity and variety of encryption methods available... and the whole "hidden volume" thing explained at this link is just totally nutty... and BRILLIANT!!!

Thanks a bazillion Halo! :highfive

(one question though.... is there a downloadable PDF of the documentation for TrueCrypt? There's a TON of info at their documentation link and it would be great to have it all in one download that could be printed out if desired; I've poked around the TrueCrypt site and can't seem to find a PDF, but maybe I've missed something obvious; I'm pretty good at missing the obvious sometimes LOL )