I2P is an anonymizing network, offering a simple layer that identity-sensitive applications can use to securely communicate. All data is wrapped with several layers of encryption, and the network is both distributed and dynamic, with no trusted parties.
Many applications are available that interface with I2P, including mail, peer-2-peer, IRC chat, instant messaging and others.
Enjoy your anonymity and privacy!
more infos on:
http://www.i2p2.de
http://eng.anarchopedia.org/I2P
http://en.wikipedia.org/wiki/I2P