The Desert Mermaid

This is actually kind of an old idea. I remember reading about it in Scientific American back in the '90s. It exploits a technicality: the spaceship isn't moving, the area of space containing it is, and since space has no mass it has no inertia and no speed limit. Tossing the extra dimensions from string theory into the mix may be new, but doesn't really address the fundamental problem of how do you get spacetime to warp like that in the first place?