Probably not going on to University.
Though had I done so I wouldn't have met & married Mrs Nelson, and I'm doing pretty well job-wise without it. I'm half way through a professional qualification at the mo and that'll give me a pretty strong degree when I'm finished.
I guess I regret missing out on the social aspect of the whole Uni thing, but then again, I probably spent the 3 years I would have been there doing exactly the same (drinking, smoking, women, etc) but earning money at the same time.
Maybe I have no regerets after all, I don't know...