Every once in a while I go out for beers after work with some of the guys that I know, and almost always there is somebody asking what the "next one" technology is; the one that is somehow going to carry him until retirement. That could be practical thinking, but absolutely nothing makes me sadder to hear. We live in a golden age, an age where great ideas and phenomenal code literally flows freely around us. Our generation was lucky enough to live through the dotCom boom and see endless opportunities, and now we are 15 years from age 65 with so many languages and paradigms out there that I fear I will never have enough time to learn them all, even in a cursory way.
Go back to school. Be the guy that does every exercise in SICP, TAs the course in data mining, and can still tell the guys in your study group what it was like to edit Pascal on a DECwriter II.