TrueCrypt is a 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 it as a real disk.
– Encrypts an entire hard disk partition or a device, such as USB flash drive.
– Encryption is automatic, real-time (on-the-fly) and transparent.
– Provides two levels of plausible deniability, in case an adversary forces you to reveal the password:
1) Hidden volume (steganography).
2) No TrueCrypt volume can be identified (volumes cannot be distinguished from random data).
– Encryption algorithms: AES-256, Blowfish (448-bit key), CAST5, Serpent, Triple DES, and Twofish.
– Mode of operation: LRW (CBC supported as legacy).
Download: TrueCrypt 6.3a