You probably already heard about Tor, if not you might want to take a look at the tor website hosted by the electronic frontier foundation. Tor is basically a freeware application that anonymises your internet traffic by routing every request through a chain of encrypted servers. There are that many chains that no server does know the source of the request and at the same time the destination. The destination only recognises the request from the Tor server, means your ip is not revealed in that progress.