I just had alook at www.i2p.net. Opening Words:

"I2P is an anonymous network, exposing a simple layer that applications can use to anonymously and securely send messages to each other. The network itself is strictly message based (ala IP), but there is a library available to allow reliable streaming communication on top of it (ala TCP)"

This may all be very good, but what it has has to do with p2p file sharing I have no idea ..... oh and btw I'm not going to continue reading or contributing to this thread!