Hi everyone,
We developed some vandal control tools over at Wikia that we thought people might be able to use/expand on. We've had these running on the site for the last 1-2 months and they've been working well for us. Basically, we made some special pages where you can specify regex expressions to block usernames, ips, and article spam. The blocks can have time limits that you can set to expire or run forever. For our purposes these had to work across multiple wikis. There's a README in each directory and documentation included in both html and wiki exported xml format that explains the function and includes SQL for creating the appropriate tables.
http://svn.wikimedia.org/viewvc/mediawiki/trunk/extensions/RegexBlock/
http://svn.wikimedia.org/viewvc/mediawiki/trunk/extensions/SpamRegex/
this one is basically a common file needed for the two above.
http://svn.wikimedia.org/viewvc/mediawiki/trunk/extensions/SimplifiedRegex/
Thanks, John Q.