  In this brief review I discuss ways and tests of CPT-Violation in the context
of quantum gravity theories with space-time foam vacua, which entail quantum
decoherence of matter propagating in such backgrounds. I cover a wide variety
of sensitive probes, ranging from cosmic neutrinos to meson factories. I pay
particular emphasis on associating the latter with specific, probably unique
("smoking-gun"), effects of this type of CPT Violation, related to a
modification of Einstein-Podolsky-Rosen (EPR) correlations in the entangled
states of the relevant neutral mesons. I also present some semi-microscopic
estimates of these latter effects, in the context of a specific string-inspired
model of space-time foam ("D-particle foam").
