  Non-WIMP dark matter candidates include particles motivated by minimality,
candidates motivated by experimental anomalies, and exotic possibilities
motivated primarily by the desire of clever iconoclasts to highlight how truly
ignorant we are about the nature of dark matter. In this review, I discuss
candidates that are not WIMPs, but nevertheless share the same theoretical
motivations as WIMPs and also naturally have the correct relic density. There
are two classes: superWIMP dark matter, where the desired relic density is
inherited through decays, and WIMPless dark matter, where the dark matter's
mass and couplings scale together to maintain the desired thermal relic
density.
