I share office space with Andrew - didn't actually know he'd been at a bank, but I can verify that he seems pretty happy to be doing what he's doing.

I never worked full time at a bank, but I did a summer internship in Goldman's tech division and the work was extremely boring. I didn't really get the impression that anyone on my team was having fun, with the possible exception of my manager. I'm sure there are some tech jobs at the big banks which are fun, but I think they're the minority.