Over 400 hundred exoplanets have already been observed in the last decade. Multitudes of asteroids, Kuiper belt objects and other planetesimals are currently being studied in the Solar system. New missions are likely to multiply the numbers of these objects in the coming few years, adding observations of terrestrial planets, planetary systems at different regimes than those probed today, and multiple planetesimals in the Solar-system. Our theoretical understanding of the formation of such objects, however, is still confronted by many difficulties. I would present a few overlooked topics in planet formation. These could both raise additional difficulties and challenges to our understanding, as well as suggest new clues and open novel directions for both the theoretical and observational studies of exo-planets and Solar-system bodies. I will focus on the contribution of binary stellar evolution to the formation of second generation planets, which may open new horizons in the search for exo-planets and the study of the coupling between planet formation and stellar evolution. If time allows, I will also touch upon some work in progress on a few overlooked topics in planet formation, including the role of aerodynamical shearing in planetesimal growth, the role played by binary planetesimals in planet formation, as well as the evolution of such binaries.
