Enterprise-grade Linux: Five network security FOSS apps
iTWire has a story detailing five open source security applications:
http://www.itwire.com/content/view/16246/1141/1/0/
As more security applications are gobbled up by large firms, open source projects gain a unique advantage. Anytime an organization needs to make money, they are willing to draw a gray line with respect to their ethics. As most open source projects don't rely on corporate funding, they can be more strict with respect to what they call malware. It is quite likely that as the volume of malware increases, this advantage will become more clear.
Growing virus production taxes security firms
The Register points out the current problem with growing malware trends:
http://www.theregister.co.uk/2008/01/25/malware_surge/
The rate at which malware is growing is quite alarming. If this trend continues it will become impossible for anti virus firms to keep ahead of the wave. The current attitude toward malware is to take a very reactive approach. Most groups don't focus on stopping the cause of problems, but rather treating the symptoms. While there is certainly a great deal of money to be made in treating symptoms, the well is going to dry up eventually.