it's always confused me why anyone would make the conscious decision to run an operating system that has no compatibility with anything
1: It's often faster.
2: It's often lighter weight.
3: Almost everything is open source.
4: Linux is good for many types of open source development.
5: Wine.
6: There are plenty of things Linux can do that no other OS can.
7: It's quickly becoming more popular - if nobody supports it, it will fail.
8: It's open source itself.
9: Highly customizeable.
10: Free (usually).
The list could go on, but I feel this explains it pretty well.