I consider models of light super-weakly interacting cold dark matter, with O(10) keV mass, focusing on bosonic candidates such as pseudoscalars and vectors. I analyze the cosmological abundance, the γ-background created by particle decays, the impact on stellar processes due to cooling, and the di-rect detection capabilities in order to identify classes of models that pass all the constraints. In certain models, variants of photoelectric (or axioelectric) absorption of dark matter in direct-detection experiments can provide a sensi-tivity to the superweak couplings to the Standard Model which is superior to all existing indirect constraints. In all models studied, the annual modulation of the direct-detection signal is at the currently unobservable level of O(10~(-5)).
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