At this week's LinuxWorld trade show in San Francisco, the hackers, administrators, and open source gurus who usually attend the event will have some unlikely companions, including representatives from Sun Microsystems and Microsoft, two companies that stand the most to lose if Linux is successful. Both companies have sent teams of people to the show before, but this year's event is a bit different, since both companies are now active and formal participants in the show and not just silent observers. But Sun's and Microsoft's approaches to the Linux threat are also a bit different, with Sun seemingly embracing a technology similar to that its been selling for decades, and Microsoft extending a cautious olive branch to a community it has been openly trashing for the past few years.

Sun's move into the Linux space seems to make sense. The company markets its own UNIX variant, called Solaris, which runs on the company's high-end UltraSparc platform; a low-end Intel-based version was canceled last year when the company announced that it would create a Solaris-compatible Linux distribution for Intel-based systems. At LinuxWorld, Sun is touting a new line of low-cost Linux-based servers and its new Linux distribution for low-end servers and desktops, called Sun Linux 5.0. The products will help Sun counter IBM in the server space and Microsoft on the desktop, the company says. "IBM is the air war and Microsoft is the ground war," says Sun executive VP Jonathan Schwartz.

After alternating between secret and open attacks on the Linux community for about four years, Microsoft has apparently adopted a new tactic as it attempts to push aside the impression that Linux represents a valid low-cost alternative to Windows. This new tactic involves open discussion with the Linux community and software interoperability, and it began with last summer's appearance by Microsoft Senior VP Craig Mundie at an open source conference. At LinuxWorld, the software giant's booth is sure to be controversial, since Microsoft has little software or services to offer the Linux community, and not much else is currently in the works. The company says it has no plans to port its popular Office suite to Linux, for example, though such a port was secretly tested two years ago when Microsoft was unsure of its Linux plans. But Linux never took off on the desktop, and likely never will, curtailing any need for such a product.

This week, however, the six Microsoft employees that man the company's booth at LinuxWorld will get a taste for what it's like to be the minority. It should be an interesting learning experience.