A world where, instead of aging in years, the people age in knowledge. So, instead of dying once a general age was reached, they die once they achieve a certain amount of knowledge. A man could live forever if he never learned anything, or could die after reading a few choice books. Of course, the knowledge of the land would be regulated, like medical drugs.
Maybe in the future, you can earn money by allowing yourself to be possessed by the genius loci of Taco Bell. And then it just spews ads out of your mouth during all the times you aren't using it.