On-the-fly encryption software which can create a virtual encrypted disk within a file and mount it as a real disk. It can also encrypt a hard disk partition or storage device, such as USB flash drive. Moreover, TrueCrypt supports plausible deniability.

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TrueCrypt - IMPORTANT: Official TrueCrypt distribution packages can be downloaded only from www.truecrypt.org (above, select 'Project' > 'Web Site')
Last Update: Nov 02 2005