TrueCrypt
Publisher: TrueCrypt Foundation
TrueCrypt is a free open source on-the-fly encryption (OTFE) program for Microsoft Windows 2000/XP/2003/Vista and Linux. It can create a "file-hosted container" which consists of an encrypted volume with its own file system, contained within a regular file, which can then be mounted as if it were a real disk. TrueCrypt also supports device-hosted volumes, which can be created on either an individual partition or an entire disk.
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, Serpent, and Twofish. Mode of operation: LRW.



