Internet Spam Filtering

• Anti-Spam SMTP Proxy (ASSP)  - Open source platform-independent SMTP Proxy server designed to eliminate spams by implementing whitelists and Bayesian filtering.
• Block Disposable Email Addresses  - Online service for detecting and preventing fake, temporary, or disposable email accounts.
• Bopspam  - Online spam filtering that works with any ISP using a POP3 mailbox, works without software installation, and provides users the ability to add their own spam filter settings.
• CleanMyMailbox  - Automated, whitelist-based email filtering that requires no software to install nor configurations to make.
• Distributed Checksum Clearinghouses (DCC)  - Anti-spam content filter that works on multiple operating systems offered for free use to organizations that do not sell filtering services or devices.
• Fassim  - Forum spam prevention solution. Presents a documentation and a frequently asked questions section.
• Fast PC Networks Spam Filter Service  - Offers high availability spam and virus filtering services for business email domains. System is redundant with filters colocated in data centers in different regions of North America.
• MailArmory  - Customizable turnkey service that filters spam and prevents malicious email, serving the needs of ISPs and hosting professionals.
• MailFilterPro  - Email spam and virus filtering service available in basic, enhanced, and enterprise packages.
• Outlook Express Tutorial: Filters  - Step by step guide to activating MS Outlook's filter feature. Includes screenshots.
• SpamAid  - Features an easy-to-use MS Outlook add-on to protect user's inbox against spam. Features include Bayesian filtering technology, auto-learning abilities, quarantined e-mails, and more.
• SpamBayes  - Bayesian spam prevention classifier written in Python for Windows, Mac, and Linux systems.
• SpamCop  - Spam reporting service with news groups and support forums.
• Webroot  - Managed email filtering service that includes archiving, image scanning, anti-virus, and encryption.
• Xeams  - Free email server and spam firewall running on any operating system. Provides web-based administration, message archiving, and SMTP, POP3, and IMAP features.