Você pode querer olhar para isto: Tor . É praticamente o método mais seguro disponível. A página da Wikipedia pode explicar melhor.
Tor is an implementation of onion routing: The service works by relaying communications through a network of systems run by volunteers in various locations. Because the internet address of the sender and the recipient are not both readable at any step along the way (and in intermediate links in the chain, neither piece of information is readable), someone engaging in network traffic analysis and surveillance at any point along the line cannot directly identify which end system is communicating with which other. Furthermore, the recipient knows only the address of the last intermediate machine, not the sender. By keeping some of the network entry points hidden, Tor is also able to evade many internet censorship systems, even ones specifically targeting Tor.