CryptoChat

CryptoChat is an easy-to-use encrypted chat program, allowing you to talk to contacts just like any other instant messenger. Featuring automatic public-key exchange and encryption with the Blowfish algorithm, this program is designed with the intention of providing the highest level of security. It implements public-key cryptography, and uses the Diffie-Hellman key exchange protocol to establish a random session key for communications. CryptoChat uses the IRC (Internet Relay Chat) system to communicate, and can also be used in an 'unencrypted' mode as a standard IRC client.