eSecurity Planet 
A resource for daily information on e-security targeted to IT managers. The site provides users with information from a variety of sources, including experts at security product and services firms, and the consultants who follow the security industry.

Microsoft TechNet: The Antivirus Defense-in-Depth Guide
Although many organizations have deployed antivirus software, malicious software such as computer viruses, worms, and Trojan horses continue to infect computer systems around the world. There is no single reason for this apparent contradiction, but the current situation indicates that the standard approach of deploying antivirus software on each computer in your environment may not be sufficient.

Open Networks Today
Networking news moves at a fast pace, and Open Networks Today lets you keep up with it. Open Networks Today offers its readers the ability to control how news is presented through customizing content filters, discussions, and news feed links.

Webopedia's "Did You Know?" Article
The Difference Between a Virus, Worm and Trojan Horse.