Left the fire department and moved to DC (wish I had done it a few years earlier). The best career move I've made.
Dated much younger girls (didn't start doing that until I was 30). It's harder to do when you're under 25-ish, but I've gone back and forth w/ girls around my age and girls 8-12 years younger (I'm almost 44 years old). Woman just don't age as well as we do (God bless em!).
Decided to never have a car payment ever again (paid off my last car payment when I was 31 years old, haven't had a car payment in about 13 years....and never will). "People who are rich don't have car payments" - Dave Ramsey (some of the simplest investing/money advice I've ever heard).