  Recently there has been much interest in hidden sectors, especially in the
context of dark matter and dark forces, since they are a common feature of
beyond standard model scenarios like string theory and SUSY and additionally
exhibit interesting phenomenological aspects. Various laboratory experiments
place limits on the so-called hidden photon and continuously further probe and
constrain the parameter space; an updated overview is presented here.
Furthermore, for several hidden sector models with light dark matter we study
the viability with respect to the relic abundance and direct detection
experiments.
