  We show that non-perturbative entities such as solitons and instantons
saturate bounds on entropy when the theory saturates unitarity. Simultaneously,
the entropy becomes equal to the area of the soliton/instanton. This is
strikingly similar to black hole entropy despite absence of gravity. We explain
why this similarity is not an accident. We present a formulation that allows to
apply the entropy bound to instantons. The new formulation also eliminates
apparent violations of the Bekenstein entropy bound by some
otherwise-consistent unitary systems. We observe that in QCD, an isolated
instanton of fixed size and position violates the entropy bound for strong 't
Hooft coupling. At critical 't Hooft coupling the instanton entropy is equal to
its area.
