Maximal energy extraction through information gathering

We calculate the maximal non-equilibrium work that can be extracted from any mass using information about its micro-state. This is done through the use of black hole thermodynamics in the context of the thermodynamics of information. The non-equilibrium work that can be obtained by knowing the exact micro-state is found to be $\frac{1}{2}M{c}^2$. This is calculated using the entropy of an eternal, uncharged, non rotating black hole. This is derivation helps elucidate the relativity of entropy and its relationship to general relativity and time.