Remember the freaky penguins from those beer commercials for a certain brand of \u201cice\u201d beer? (For that matter, remember the whole \u201cice beer\u201d marketing phase? If not, good.)This particular campaign - with the catch phrase \u201cbeware of the penguins\u201d - involved CGI-animated arctic waterfowl, ominously knocking on the door of unsuspecting \u201cice\u201d beer drinkers. The idea, I guess: Penguins, who like ice, want to steal your ice beer.Ok, then.Well, the penguins are back. But they\u2019re knocking on the doors of corporate data centers this time. For years, Linux software was used in the periphery of business networks as group file and print servers, and as a workhorse in the demilitarized zone (DMZ), in Web serving and security roles.This year, expect Linux to break out as a platform for running core applications for businesses. That\u2019s why Network World picked Linux as one of our \u201cSix Technologies for 2006.\u201d Go to NetworkWorld.com next week to read about two companies already well on their way to making Linux the centerpiece of their respective application strategies.The Cambridge Health Alliance, a Cambridge, Mass. healthcare management firm, made the Linux switch over a year ago for one of its key patient care applications; now the organization has one big question for any apps vendor coming in for a meeting - \u201cdoes this run on Linux?\u201dCommerzbank, one of the largest financial institutions in the world, made the jump to Linux when it found the amount of software available for its Tru64\/Alpha systems to be scarce. The bank now runs its entire Oracle applications suite on Linux serving tens of thousands of employees worldwide.IT executives from Cambridge Health Alliance and Commerzbank both said they encountered some wariness of the penguin when trying to sell their Linux plans to senior management. Cost savings, performance increases on Linux pilot deployments, and surging support from major IT vendors helped push these Linux migrations through.