The Invisible Internet Project (I2P)

The I2P network is a fully encrypted peer-to-peer overlay network. An observer cannot see a message's contents, source, or destination. No one can see where traffic is coming from, where it is going, or what the contents are. Additionally I2P transports offer resistance to recognition and blocking by censors. Because the network relies on peers to route traffic, location-based blocking is a challenge that grows with the network. Every router in the network participates in making the network anonymous. Except in cases where it would be unsafe, everyone participates in sending and receiving network traffic.