You see I can't answer as it's more than one. That's why I do qualitative research ;-)

Someone I know who uses Linux promotes Zetoc all the time. He loves it. It's freeware too. (It does also work on Windows and Mac, I believe)

Because I always wanted to but never thought I would have the opportunity
So I could work as a lecturer
So I could inspire people like I was once inspired (perhaps cheesy but true)
So I could do a job where I am allowed to use my brain, and think the way I like to think, and where that is valued and rewarded
So I could have a job I wanted and feel happy, and not just go to work because I have to
And, of course, so I can call myself Dr!

(These are the things I am trying to tell myself, and need to remind myself of more)