| In Sid Meier's Alpha Centauri (SMAC), the Theory of Everything is a Secret Project. It may be built at a cost of 360 minerals, on discovery of Unified Field Theory (C7). It doubles Lab research output at the base where it is built.
This is the same effect as the Supercollider Secret Project, but costs 1/3 more. I rate the Supercollider a "mediocre value" for the cost, and the same goes for Theory of Everything.
If you have the luxury of pursuing this 'Project, the same notes apply for maximizing its effect: build in a base with extra Energy resources, one with existing Research-enhancing facilities (e.g. Biology Lab, Network Node); prioritize further production with stress on more Research-oriented facilities; and keep population high (that is, avoid producing Colony Pods) at that base.
A "theory of everything" is something of a philosophical Holy Grail. In that historical quest, we've seen Unified Field Theory, Grand Unification Theory, Quantum and Superstring theory, and of course there have always been scientifically null theories like Creationism. SMAC's ToE is presumably one that stands tests of mathematical integrity and experimental validation.
Secret Project animation narrative:
"The Earth is the cradle of the mind, but one cannot stay in the cradle forever."
-- Konstantin Tsiolkovsky,
The Father of Rocketry, Datalinks | 
