Introduction - Why Macs?
I work as a System Administrator for a Computer Science Department and as a result I manage both server machines and lab machines. Some time ago the department decided (and I was in agreement) that it would be a good idea to offer the students additional variety in the computer lab by replacing some of the "Pee Cee" machines in the main undergrad lab with some Apple Macintosh systems. This would give students access to Mac OS X (pronounced "ten") in the lab in addition to Linux and Microsoft Windows.
Although Apple switched to Intel-based machines a few years ago, you can't just run their OS on any Intel/AMD machine as they have both licensing reasons and technical reasons why their OS should ONLY run on Apple hardware. They don't seem to be friendly to running Mac OS X inside of Virtualization either. Mr. Jobs, why do you hate us? I digress.
The first three years we had Macs in the lab they only ran Mac OS X and as time passed, fewer and fewer people used them. The usage slowdown was caused by a number of reasons that I'll not go into here. This year though, I decided not to give up on the Macs and to make them triple-boot... so if people don't want to use Mac OS X they don't have to, and the machines can get better utilization.