It's a fascinating field of research, but it will probably always remain theoretical.
It more than likely will happen way beyond our lifetime. Which begs the question, why haven't we been visited by time travelers? And if we have, would we even know about it? Would they even be able to visit this "past" or some other parallel past?
For other theories that have been now recently proven, read up on the Einstein Condensate, and the status of quantum teleportation.
