There were suggestions that the antimatter-matter asymmetry is because antimatter was preferentially segregated into a dense phase of hadronic matter, like quark matter nuggets. This would be interesting because if such nuggets could be found and captured, they'd be a potential source of energy by annihilation with ordinary matter.
It has the nice feature of explaining why the density of baryons and the density of dark matter are not too different. Naively, there's no reason to expect the two to be anywhere close to each other. It also offers an explanation for the observed matter-antimatter asymmetry in the universe.
Don't believe any theory until it's been well tested.
