How will a Theory of Everything or a Grand Unified Theory affect the way we live?

Einstein is said to have “wasted” second half of his life in trying to ignore Quantum Mechanics and come up independently with a Grand Unified Theory that would explain all the four basic forces of nature and unite the laws of both the very small (presently governed by Quantum Mechanics- and encompassing weak force, strong force and electromagnetism) and the large(governed by Relativity and describing gravity). Some of us think that maybe with additional dimensions and string theory, we will have our theory of everything finally, and are looking forward for some big evidences from LHC, CERN.
Some others send us shivering by telling that there might be other basic forces than the 4 known.

Anyways, suppose we do find this Grand Unified Theory, how will it affect the way we live daily?