It's interesting that one of the seminal events in the history of Sun Microsystems isn't included in its official corporate history. But without question, Sun would not be the company it is today had it not purchased--for pocket change--the Unix server business of Cray Computer in the summer of 1996.

At the time, Sun (nasdaq: SUNW - news - people ) was a $7 billion company not even in the high-end server business. It had mainly stuck to its knitting as a leading seller of Unix workstations. But when workstation rival Silicon Graphics bought Cray, it created a problem for SGI. That's because Cray was a licensee of Sun's SPARC processors and Solaris software and sold high-end servers based on that technology. If SGI held onto that part of Cray, it would be lining the pockets of one of its biggest competitors. It needed to sell the unit--and Sun was only too happy to buy it.

Sun's Purchase Of Cray's Unix Server Business