Simply right-click on a file in Windows Explorer and you can encrypt it, and a double-click decrypts the data. AxCrypt also supports self-decrypting files so that you can protect files in transit while still allowing e-mail recipients to view the information easily. Operating System: Windows.
As you might expect, Mac GnuPG ports GnuPG so that it can be used on a Mac. It provides better privacy than PGP and supports multiple encryption standards and languages. Operating System: Mac OS X.
Short for "Windows Privacy Tools," WinPT collects a number of different encryption tools into a single application. It's based on GnuPG and is compatible with PGP. Operating System: Windows.
This archiving utility creates, opens, and encrypts zip files and dozens of other compression formats. Additional features include split/join files (file span), wipe files (secure deletion), compare, checksum and hash files, system benchmark, and more. Operating System: Windows, Linux.
Intended as a replacement for the Unix crypt, MCrypt lets developers add a wide range of encryption functions to their code without needing to be expert cryptographers. Note that this is a developer tool, not an encryption app for end-users. Operating System: Windows, Linux, Unix.
Store secret data securely on your Palm-based handheld. Keyring provides secure triple-DES encryption and is available in a number of different languages. Operating System: PalmOS.
23. Hide in Picture
Conceal data within normal-looking bitmap images. A simple password decrypts the file. Operating System: Windows, DOS.
Steghide compresses, encrypts, and conceals messages inside pictures or audio files. It also embeds a checksum to verify data integrity once decrypted. Operating System: OS Independent.
This e-mail relaying server signs or encrypts e-mail communications using GnuPG (Gnu Privacy Guard) and your existing e-mail client. The developers are careful to note that this app only protects e-mail in transit--it is still stored in its decrypted state on your computer. Operating System: Windows.
MailCrypt allows you to encrypt, decrypt, and sign messages and usenet articles using either PGP or GnuPG. One warning: MailCrypt may not be secure when used on an NT workstation (site has details). Operating System: OS Independent.
27. Open Signature
This digital signature project supports all Open SC cards and aims to be the first single app that can be used with cards from multiple countries. Open Signature originally focused on cards used in Italy but has branched out. Operating System: Windows, Linux, Unix.
Ultra-fast and lightweight, Crypt can be used encrypt or decrypt just about anything on your Windows system, including regular files and directories, consoles, communication resources, disk devices, and more. Operating System: Windows.
WinSCP supports both SFTP and FTP file transfer. It also offers a basic file manager. Operating System: Windows.