In year 2005, IBM had total revenue of $91.1 billion. It is all based on AIX 5L operating system, but their 60% is service revenue. AIX 5L started as Unix but added Linux capability thru several cooperation with Linux distros. TurboLinux, RedHat and Suse, mainly.

It is the service to IT departments that made IBM larger. It operates like an insurance against breakdowns. IBM informs the company involved what their budget should be for IBM service next year. Many hardware may even not be IBM manufacture. So, IBM profit margin suffered in recent years.

Nevertheless, the Linux market is larger, when service had to install new equipment for any company growing their supply chain software, Linux or not.

Smaller IT companies do well to study the IBM model of computer business. Many IBM alumni had shaped some of IBM competitors to great companies. Some of them, we like to invest and grow with them.

Next thing we know, Microsoft may enter the service field and protect their turf? Because of their leadership in auto-update and error report if crashed, their unique position to prevent breakdowns in hardware and software made service smooth and silent administrator easy piece of work.