1on1mail - Free email software that allows users to send and receive email through a secure network that utilizes military spec (2048 bit) encryption.

TenFour - Designers of the TFS Secure Messaging Suite, which acts as a messaging firewall and is a single point of control for managing messaging security. Offering security features such as encryption, key management and digital signatures.

iSolv Technologies TSPMail - Provides security for e-mail communication without modification to existing software or network components through the use of Microsoft Winsock2 technology.

Zixmail - Web based messaging offering secure delivery. Registration required by the sender and recipient. PC Magazine's Editor's Choice award. Compatible with other web based mail services. User does not have to change email accounts.

PostX - Provides secure Internet-based solutions that enable businesses to confidentially deliver high-volume, high-value information to each customer using Email and the Web.

Zip File Encryption - Software to encrypt/decrypt/shred zip files for emailing. Recommended by PCWorld. Provides archive facilities and the built in compression feature makes for smaller files for transmitting.

Ensuredmail - Ensuredmail is a client side application that encrypts emails and files. Compatible with Outlook. Free download available.

LexiGuard - PKI-based, RSA-secured data protection software generating its own digital certificates and keys. Ideal for stand-alone applications, scalable and offering emergency recovery passwords.

Secure Encrypted Messaging - Web based ASP messaging company offering hosted services and software. The PMKey server supports secure login, sessions and delivery. Encryption is 128 bit backed by Entrust. Web based, POP and WAP access: encompassing a mail client look and feel with moveable frames, folders and the ability to identify web bugs and foreign scripts. ASP source code available for UI customization.

Zendit - Free one-click encryption for Outlook or any web-based mail using IE and Windows 95+. Download-able client software.

Web Based Secure Delivery from Etekmail - Secure delivery for individuals and businesses. Can be used with an existing email account. 90 days free trial.

Three ways of email encryption - Choose the best way of email encryption

CryptoHeaven - Premium secure instant messaging, chat, online data storage, file sharing and email using 256 bit encryption. Free download offering 2MB of storage. Upgrades of storage and bandwidth are available.

Labcal Technoliges - IsoShieldMail - Lotus Notes Plug-In for exchanging secure mail using Entrust's PKI technology.

PEEPLock - Encryption and decryption software for multiple files & folders. Passwords can be text or images. Maillock is compatibe with email clients: Euroda and Outlook. Free demo, upgrade for additional users and MB transfered.