Optical nonlinearities influence the dynamics of light on all spatial scales. Light can be switched on a few micrometer length in nanophotonic devices, as we have demonstrated recently. The interplay between group velocity dispersion and optical nonlinearity gives rise to a lot of other interesting phenomena which go far beyond simple switching. Based on a fiber loop set-up we could realize soliton formation, self-acceleration and super fluidity of light at mW power levels and for propagation distances reaching thousands of kilometers.