Barracuda Networks Barracuda Networks Spam Firewall 300 2.2.3, Sophos Sophos PureMessage 4.5, and Greenview Data's Greenview Data SpamStopsHere are among 10 reviewed spam filters. The others are Vircom modusGate; BorderWare MXtreme Mail Firewall Appliance MX-400 3.1; Proofpoint Protection Server 1.5; Brightmail Anti-Spam 5.5; Katharion Anti-Spam for Businesses; IronPort C60; and Espion Interceptor 1.3125. Spam Firewall 300 2.2.3 is the editors; choice, especially for very low cost enabled through the use of off-the-shelf hardware and various open-source applications, including SpamAssassin running on a hardened Linux kernel. Applications are integrated through a unified Web management interface. Barracuda was among the easiest products to get up and running and to administer. Testers could set spam-scoring thresholds to tag, quarantine, or delete spam, based on the likelihood of spam. Tests showed that users do not need an IT department to management Spam Firewall 300 2.2.3. Vircom modusGate 3.0 was rated almost as highly as Spam Firewall 300 2.2.3, but it had a slightly higher false negative measurement and finished in second place in nonweighted accuracy. Accuracy test results are listed for 23 products in total, 13 of which did not qualify for review. The ten products reviewed were compared for platforms, antispam engine technologies, antivirus engine, management, delegated administration, mail server access, management interface, security certification, reporting, high-availability/scalability, and cost. Spam Firewall 300 2.2.3 had the lowest cost by an extremely wide margin based on user per year for 1,000 users and for 10,000 users.