- SFDE - Spam Filter Distributed Email Database
- SFDB - Spam Filter Distributed Blacklist Database
- SFDC - SpamFilter Distributed Content Database
- Detection of spam signatures in images
- RBL and SURBL Blacklists
- Greylisting
- Bayesian statistical DNA fingerprinting
- SSL and SMTP Authentication
- SPF - Sender Policy Framework
- Block Emails from User-Defined Countries
- ...and dozens of more filters!