I believe "Nostratic" is the name given to the supposed super-language family that some researchers claim to have reconstructed, going back thousands of years earlier than the stage of Proto-Indo-European or Proto-Afro-Asiatic.
http://www.sumerian.org/prot-sum.htm provides some interesting reading. Everything here is from the viewpoint of a Sumerian language scholar looking "out", and not just that of a scholar of languages looking "in".