ContentBox sports many out of the box comment moderation tools.

From the screenshot you can appreciate all the different tuning you can do for comment moderation:
- All comments moderated
- User must have an approved comment to be approved consequentely
- Auto-deletion of comments that are moderated
- Moderated keywords (ip addresses, authors, emails, or content)
- Blocked keywords (ip addresses, authors, emails, or content)
My favorite setting is the auto-deletion of moderated comments. I have never ever ever ever cleaned up spam anymore. I let ContentBox do it every X number of days and I truly appreciate that as it is one less thing to worry about.