Freenet is a free program that lets you publish and obtain information on the Net without needing intermediaries and with total freedom. How is it done? Well, it uses a completely decentralized system, both for publishing and for downloading.
All communication in the Freenet nodes is encrypted, and each user contributes to the Net giving bandwidth and a little of their hard drive where data is stored. The only difference with P2P system programs is that in Freenet it isn`t the user who chooses where data is stored. Files (always encrypted) are kept or deleted automatically from the program depending on their popularity.