http://www.truecrypt.org/Open-source free on-the-fly disk encryption for Windows, Mac OS and GNU/Linux. It can encrypt partitions or create virtual encrypted disks within files. Implemented ciphers: AES-256, Blowfish (448-bit key), 3DES, Serpent, Twofish. Provides plausible deniability.TrueCrypt is free open-source disk encryption software for Windows 7/Vista/XP, Mac OS X and Linux. In case an attacker forces you to reveal the password, TrueCrypt provides plausible deniability. In contrast to file encryption, data encryption performed by TrueCrypt is real-time (on-the-fly), automatic, transparent, and does not involve temporary unencrypted files.
Free open-source disk encryption software for Windows 7/Vista/XP , Mac OS X, and Linux
Creates a virtual encrypted disk within a file and mounts
Encrypts an entire partition or storage device such as USB flash drive or hard drive .
Encrypts a partition or drive where Windows is installed (
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