From the website:
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.
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.
So the client is a "friendly-fork" of Gaim, it uses Tor to achieve anonymity, and for the crypto parts (secure messaging, secure file transfer) ScatterChat uses libgcrypt.
It's a cross-platform application available for Linux, Windows; support for other OSes is planned (Mac OS X, others).
You can always download the source code, of course, as it's free software. Actually, not quite. While ScatterChat itself is based on the GPL'd Gaim, it has to be GPL'd, too. However, the scatterchat-module package, which seems to contain the crypto-parts, is licensed under a custom "Hacktivismo Enhanced-Source Software License Agreement" (HESSLA) right now, which is so horribly long I didn't even bother reading it.
However, the README says:
I am open to the possibility of re-licensing parts of this library to GPL, BSD, public domain, or some other license. I cannot make any promises, but I will try to accomodate reasonable requests.
I'm going to do just that, email the author and ask him nicely to change the license to some sane, well-known free software license. If you feel similar, please let the author know (hint, hint). Depending on what the HESSLA really says, it might prevent ScatterChat from entering Debian, for example.
I haven't yet tried to use the application, but it sure looks like it has a lot of potential. It also seems do most security-related things right:
Of course that's no guarantee that it's secure; I hope some crypto-gurus look over it soon. But at least they didn't make obvious stupid mistakes we've all seen in many other pieces of software.
Anyways, I feel this is a real important project which will help lots of people (activists, political dissidents, normal people like me and you who value their privacy). Go check it out!
(via Boing Boing)