Lots of scientists have been researching inertial effects in an attempt to develop the "reactionless space drive" (sometimes called propellantless or self-contained space drives). Has anyone made any headway? I sometimes find articles pertaining to this that will state things like, "Professor so and so of such and such university has devised a theoretical means of self-contained propulsion." These articles will often state that the results are extremely limited (less than the width of an atom in one case) or the concept is based on the highly theoretical reseach of so and so (meaning it's probably garbage to begin with, I suppose). Are these concepts usually developed in an attempt to verify Newtonian Mechanics with the expectation of failure, or do scientists really sense that there must be a way around Newton's laws? What's the latest news?