you can use mixminion with usenet groups too for very strong anonymity. And Tor / PIR to obtain messages. Membership concealment is where the weakest spot is going to be in our idealized system. Tor bridges + obfsproxy could be promising, if they are greatly expanded on / touched up on. But I would rather make a new remailer all together. Mixminion is outdated, there are much cooler mix designs today and I want to implement one of them . And the requirement to have external email accounts / usenet accounts etc just make it too big of a hassle for it to ever catch on. The system needs to be designed so that it is fully contained from the get go, instead of compartmentalized message transport / anonymity away from message storage and retrieval. I think high latency solutions are largely being disregarded today on the assumption that people need low latency. And it is true that you need low latency to do a lot of things. But the things we are doing don't really quire low latency, and it seems almost retarded to limit ourselves to it. Of course any solution needs a lot of users for it to be anonymous, but I think a mutli-latency messaging system would get a significant amount of usage, especially if people don't need to be bothered about managing SURBs and figuring out usenet etc. The technology to do this is already there in parts that can be pieced together by people with the technical know how (and there are some groups using these systems), but the designs for systems that can do it much better are out there too.