TrueCrypt 4.2a

Main Features:
Creates a virtual encrypted disk within a file and mounts it as a real disk. Encrypts an entire hard disk partition or a storage 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 – more information may be found here). 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). Conceived in 2003.