After a slow start, says Brian Larsen, senior product marketing manager, Enterprise Solutions, for Brocade, IBM is now incorporating Linux onto System Zs, and customers are seeing a difference in the bottom line. Now that large institutions are moving thousands of applications to the mainframe, the savings generated by removing unneeded servers, reducing maintenace and licenses, and decreasing complexity and management add up to what IBM calls ROI in 18 months to three years. Not bad. Increased efficiency in processor technology has led directly to the list of other data center efficiencies, says Larsen, with larger companies leading the way. For more companies to benefit, Larsen recommends that they examine why efficiency is in their list of top priorities, but the advantages of mainframes that would move them toward those goals aren't being maximized.