My job (writing programs used by people around the world, all from my home office in small city Michigan) could not have existed in 1973. Indeed, my house probably has computing power equivalent to that of a good-sized university of the time. A sizable percentage of the food I eat was not available anywhere outside of a Chinatown then. My favorite genre of games, role-playing games, had not yet been invented. Nor had the high blood pressure pills I take. The surgery I had at new year's would have meant days rather than hours in the hospital.

And my son could never have been born. Life-altering? Hell yes.