MailScanner is probably the better solution for those in a more enterprise like environment, as it can be installed on a broad selection of platforms and it has a bit more firepower than Scrollout F1. MailScanner is open source software released under GPL license that runs on most flavors of Linux and integrates with Linux-based email gateways. We installed MailScanner on an Ubuntu server, but this was not an easy task. As part of the install you can select to install a MTA such as Postfix or SendMail, there are also options to install SpamAssassin and ClamAV. MailScanner provides a ‘command center’ for other open source anti-spam and anti-virus tools as well as over 20 commercial offerings. We wish MailScanner had a better installation interface. However, once installed we liked how MailScanner provides great granularity for handling messages containing spam and also its ability to integrate with other products. The documentation, essentially a 400-page PDF book by the founder of MailScanner (Julian Field), is very comprehensive.