I run a spam/virus filtering email relay for some clients and I agree with most of what Richard says:
Everything that's being discussed has already been done to combat email spam. It seems the appropriate thing to do is to leverage that work instead of re-inventing it.
There is also Akismet which Wordpress users can use. I'm sure there is a lot of work that has been put into blocking spam in blog comments and email that overlaps.
I recently discovered a test wiki I had set up and forgotten about had been overrun with spam and started using it to watch the spammers and record their "work".
From these observations, I think I like Jamie Thingelstad's idea (partly
because, yes, it would persuade people to make sure their wiki is registered at WikiApiary):
On 05/24/2013 07:58 PM, Jamie Thingelstad wrote:
One thought I have had is having WikiApiary use a bot account on remote wikis that wish to participate to fight spammers, revert changes, ban them, etc.
If you could also collect urls added in reverted edits, it seems like those would be good candidates for a shared blacklist.
Mark.