But the semblance of a "monoculture," as Linux advocates sometimes derisively call the Windows environment, is starting to emerge, with all of its pluses and minuses.

Vendors at the Desktop Linux Summit are expected to unveil a new integrated server and desktop standard, which a number of leading Linux vendors, including Red Hat, Novell, the Ubuntu project and Linspire, are expected to comply with.

While Ulrich praises Novell's AppArmor for its ease of use, he said SELinux is a "pain to configure," especially for desktop users. He also pointed out that even if malware is unable to access root files and applications, it can still cause plenty of damage to files and applications. And contrary to popular belief, he said Linux may actually be more vulnerable to virus propagation by e-mail because so many e-mail programs use the same underlying application.

"Even if you use a graphical mail client like Thunderbird, it still uses Sendmail," Ulrich said. "Once the virus gets going, it can go straight to Sendmail by itself."

Some Linux users, while reluctant to install antivirus software on client computers, are starting to take more safety measures. Ritz Camera Centers Inc., which is in the process of upgrading more than 4,000 Point-of-Service terminals in stores nationwide to run Novell Linux Desktop, is taking pains to ensure the computers are isolated from the Internet, according to Bob O'Hern, senior vice-president of information systems.