Invisible Internet Project (IIP was already taken)
I2P is a project from the makers of IIP to create the next generation internet anonymizer and anti-censorship network. I2P is based on concepts from the IIP project but is meant for general anonymous IP communication rather than IRC communication like it's predecessor.
Much like MUTE each node in the network is identified by a hash which is required to connect to it. This hash, however, represents a server and not a node, so a node running two seperate servers will have two hashes, one for each server.
Because the communication is secured at the "transport layer", encryption and anonimization need not be done by the server, so simple servers like Apache can be used.