This is kind of an open post.
For grad students, current, former, stuck and lapsed: Why did you enter grad school? Has your experience so far lived up to your expectations? What did you think you wanted to do, and what are the chances of doing it? Share yours and I will mine.
For professors, new and tenured: Same question. Was grad school worth it? Is it all you imagined? How important do you consider what you do?
For those in the corporate/"real" world: Are you happy? Did you choose your career/job or fall into it? If you went to college, did it prepare you for your job? Why do you get up every day and go to work?
For all the rest: What and Why?