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.

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.

Security Focus: Detecting and Removing Malicious Code
Although some exploits are designed to announce their success (or taunt their victim), most remain quiet. As you can imagine, they stay silent for a reason: so they can conduct nefarious activity surreptitiously.

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