I was thinking about blocking of proxy IPs of anonymous editors, which may sacrifice another possilble contributor who shares the IP, but may be necessary to get rid of the very annoying vandals. I came to an idea.
Why don't we put a cookie on the anon users browsers, so they could be tracked with something more than the IP (say, an ID)? Of course it can be circumvented by legitimate anons who care about their privacy, or by serious vandals who know enough about how cookies work, but we may be able to get rid of the insisting newbie vandals (who are the guys who create the most problems for likes of me).
The idea can be extended to things like putting a cookie trap, which an admin can turn on for a certain article, which then assigns IDs to each anon contributor that edits the page, and then only block the <IP, ID> pair instead of the IP.
I know it may be hard codewise, of course.
roozbeh