Receiving anonymous messages is still an open problem. The solutions we have so far are cumbersome to operate. They also depend on a chain of machines remaining up and reliable for a long time, which is expensive. A quick solution is to use the list to send anonymous messages. It is inexpensive to tell if a message is encrypted for a key you control so it is cheap to find messages you can read. The nice thing about this solution is that it is quite difficult to make a complete list of cypherpunk recipients given the multi-rooted "tree" structure of the list. There are leaves in many countries. Even if every wire were tapped and tracked, it would be hard to guarantee that people were not moving list traffic around on diskettes. To make filtering easy for people, I would suggest adding an "X-Private-Message" field to the header. For PGP messages, the contents of this field could be "PGP-Key-Id:0xDEADBEEF". (New formats can be invented as new protocols are invented.) Some people will object to this new form of "noise" message. It should be easy for somebody to set up a subsetted version of the list which pre-filters the private messages. (Although, how anybody can read the raw list without a filter of their own is a mystery to me.) A good reason to receive the complete list is that it conceals the fact that you are receiving (or not receiving) anonymous messages. If you think you might ever in the future receive an anonymous message, this will allow you to do so without revealing it. This scheme could be attacked by actively intervening with the propagation of the list and supplying people with different messages depending on which branch of the "tree" they are on. This could be used successively to narrow the list of "suspects" receiving a certain message. There are two ways to prevent this. One is to receive the list from more than one source and compare the messages received. If many people are doing this, which is likely since each has a strong motivation to detect this attack, then the first attempts should be detected immediately. The other method is to have a trusted person post a signed list of message ids and checksums that have come down the wire every day. (Acknowledgement: This is probably a rehash of BlackNet.) Peter