Systems administration and IT is my second career. I was doing science before this.

I've seen my father, my brother, friends all launch second careers. Most of them weren't done to make a lot of money (except for my brother, who is still working at it). The vast majority of second careers won't make you wealthy, but you spend an awful lot more time making sure you're satisfied and happy. You'll tend to kiss "suffering for the cause" good bye.