* Me as a private person: ALL games, Pages (OS X application)
* Me as a professional: MS Excel, MS Outlook or other Exchange client equivalent
* My colleagues: SPSS, Nvivo, MS Outlook or other Exchange client equivalent
* My father as a professional: Adobe CS
The real reason why I don't switch to Linux on any of my computers at home: usability. Linux for the desktop is still too difficult to work with, even for a power user like me. EVERYTHING that reasonably needs to be configured has to be configurable in the GUI. You should never ever need to open a Terminal to fix things.