The Lorenz factor γ →∞ as c →∞. However if c is replaced by an imaginary number id, v can be arbitrarily large and the limit as v→∞ of γ = 0.0. If we see the speed of light, c, as a physical constant used in transforming reference frames, there is no reason to see c as an actual speed.If we instead see it as a constant with the dimensions of velocity, there is no reason not to have an imaginary analog. Nonetheless, for terminological symmetry, I call the imaginary analog of the speed of light, id, the speed of dark and explore some implications of such an imaginary physical constant. These implications include a model of the universe in which dark energy and matter are globally observable but not locally, and the possibility of faster than light communication, energy transmission and matter transmission.