Supernatural.
I'm still hoping and hoping that, in the million to one chance, Eric Kripke will one day make a prequel series to Supernatural. It would take place in the Wild West and would revolve around a gruff, whiskey-downing cowboy hunter who's an ancestor to Daniel Elkins. The series would show the origins of the mythical Colt handgun--which will have been made for this hunter--as well as the Devil's Gate railroad thing, and perhaps the hunting of the vampires to near-extinction (at least Luther's family).