MessageVortex is a protocol which is aimed to maintain the anonymity of sender and recipient of a message towards third parties. Unlike other protocols, it does not provide an own transport protocol. Instead, it hides in common transport facilities such as email (SMTP/IMAP) or chat (XMPP).
This is done by something you might call as onionized mixing. "Mixing" is not entirely true as the protocol does more. It adds redundancy information to the protocol while sending the message in chunks. This redundancy makes it next to impossible for someone to follow the message flow.
What is so special about the protocol you might ask. First, it has some unique properties due to the fact that it hides within other protocols. Therefore, all "ordinary users" of the protocol do improve hiding as they increase the mass to be analyzed. Another unique property is that it relays not on any trust into a central infrastructure. Infact, we assume malicious nodes. Third, any message transferring account may be used to send VortexMessages. No need to buid specialized servers. A smartphone or an ordinary PC can do it.
Currently published is only the draft of the RFC document. If you are interested in the projects source code, feel free to contact the website owner. There is already a working (but not yet complete) implementation available.
A reference implementation in Java will be available in the download section soon. Just give it a try.
In the meantime feel free to read the RFC draft or the other docs. They are becomming more and more stable. The protocol may be considered as final.