[mahz]

I have a decently sized/active forum and cured my spam problems, so I'll throw in my 2c:
- I don't even use vBulletin's "Spam Management" functionality.
- I use NoSpam! with two questions that cycle.
- I also use the Auto-Moderate Evading Banned Members mod which is downright amazing. It makes a new thread in private moderator-only subforum when someone registers on an IP that matches any IP on file for anyone on the ban list (or if they share a cookie). In the thread, it displays the registrant and the list of banned usernames that share the IP allowing for moderators to discuss what should be done about it.
- My registration also uses ReCaptcha, which I'm pretty sure I had to specific somewhere in the options before. Maybe it's default nowadays.

Bots can't get past the ReCaptcha + NoSpam! questions, and repeat human offenders get silently placed in moderation queue while my moderators get alerted. Works great.