Got my PhD 10 years ago, then promptly left the field. I was working in biology. Did some mind numbing research, mainly in the lab, for 4 years, counting beetle eggs. When I finished got a job in IT. The PhD gave me two things that I never had before:
1. The ability to work in detail on my own for a goal years in the future. This means you are able to handle anything that work throws at you.
2. A confidence in my own ability that I lacked before. I now know I can do anything… just need to find something that really means something to me now ;-)