0Spam.com Express 1.0
0Spam.com Express is the all-in-one, next generation anti-spam tool that protects you from the next generation of spams. Compatible with all versions of Windows and most E-mail clients, 0Spam.com Express can safely and efficiently remove spam from your existing POP3, Yahoo, Hotmail, GMail, or IMAP accounts. Integrates easily with your E-mail client and logs all scanned messages allowing you to see which messages were blocked and why.

ORF Enterprise Edition 4.2
ORF Enterprise Edition is an enterprise-level anti-spam solution that helps you to block spam before it reaches your network. ORF uses a combination of anti-spam technologies and custom filtering options to stop the spam on SMTP protocol level. ORF can be used with Windows 2000's/2003's built-in IIS SMTP Service and Microsoft Exchange Servers (2000, 2003 or 2007)

VisNetic MailServer 9.1
VisNetic Mail Server is a versatile multi-featured mail server for Windows operating systems. VisNetic Mail Server can be licensed for any size organization as well as ISP and ASP environments. VisNetic Mail Server combines a simple, easy-to-use administration console with unmatched mail server security, speed, and scalability. VisNetic Mail Server features support for Sender Policy Framework (SPF) and Spam URI Realtime Blocklists (SURBL).

AntiSpam 2.38
AntiSpam is a light, powerful and fast pop3 email spam filter and monitor. It needs almost no processor resources while it filters your pop3 accounts and inform you about incoming mails. AntiSpam is made using Assembly Language and the filtering engine is the fastest in the world. With AntiSpam you get the email you want and nothing else. Is that simple.