Looks like those crazy kids at Cult Of The Dead Cow are at it again…

ScatterChat is a HACKTIVIST WEAPON designed to allow non-technical human rights activists and political dissidents to communicate securely and anonymously while operating in hostile territory. It is also useful in corporate settings, or in other situations where privacy is desired. It is a secure instant messaging client (based upon the Gaim software) that provides end-to-end encryption, integrated onion-routing with Tor, secure file transfers, and easy-to-read documentation. Its security features include resiliency against partial compromise through perfect forward secrecy, immunity from replay attacks, and limited resistance to traffic analysis… all reinforced through a pro-actively secure design.

On the technical side, ScatterChat uses 2048-bit ElGamal and 1024-bit DSA for encryption setup and authentication. For each new conversation, ScatterChat generates a new 256-bit AES message key, a 256-bit SHA-1 HMAC key, a 256-bit nonce, and a 256-bit AES file transfer key. It is immune to replay attacks, supports Perfect Forward Secrecy, and features limited message deniability properties. If that wasn’t enough for ya, more technical details can be found here.