Worse, you have to trust the administrators on every mail routing machine on the way, as the message only becomes anonymous once it reaches my machine. Another thing is mail failures. To fix this problem, the server requires that you use a password when you try to mail to a non-anonymous user. The password can be any string of upper- or lowercase characters, numbers and spaces. If you suddenly discover that the server requires a password for posting stuff etc, somebody has managed to use your account and set a password.
Crackers are just too clever.
Please don't do anything stupid that would force me to close down the service. As I am running my own company, there is very little political pressure anyone can put on me, but if somebody starts using the system for criminal activities, the authorities might be able to order me to shut down the service. If you think these instructions are unclear and confusing, you are right.