A number of recent theoretical and experimental works indicate that microcavity supercrystals may have interesting applications. Photonic structures and metamaterials are in the focus of interdisciplinary studies, which span laser physics, condensed matter physics, nanotechnology, chemistry and information science. Many papers have been devoted to realization of light-emitting devices based on polariton crystals. In this context, semiconductor microcavities represent quantum confined optical systems featured by strong coupling of elementary crystal excitations (excitons) and the optical field. Photonic supercrystals can be built from spatially-periodic systems of coupled microcavities.