... I think the kind of setup torrent swarms use would be worse. Well, "limited in some ways it isn't currently," I guess is what I really mean. You'd also run into issues with patterns in the network traffic I'd think. Might even be trivial to tell who's buying illegal things and who isn't. One of the reasons Tor protects users is that there are so many people connecting to web sites it's not really possible to analyze the traffic in the network and see who's connecting to what. You don't have to be able to read the data to recognize certain unmistakable patterns. Break the centralized-server scheme though, and you lose the protection of everyone else whose traffic is so similar.