IT Toolbox has a great little summary of the experiences of Mike Kavis, a guy who's been living Microsoft free in an all Microsoft shop - at work! It all started from an "eat your own dog food" challenge (something i did with my wife which finally precipitated the switch to Linux on her part). Check out his other articles in the series:
- Still afraid of open source?
- Open Source and loving it!
- Open Source and Microsoft Free
- Comparison of Linux distributions
Kavis also links to a nice little article about what happens when you switch to Linux (specifically Ubuntu).