We discuss the notion of gap distributions of various lists of numbers in [0, 1], in particular focusing on those which are associated to certain low-dimensional dynamical systems. We show how to explicitly compute some examples using techniques of homogeneous dynamics. This works gives some possible notions of `randomness’ of special trajectories of billiards in polygons, and is based partly on joint works with J. Chaika, J. Chaika and S. Leliever, and with Y.Cheung.