My understanding is that this "see through the vehicle" capability is built into at least some helmet-HUD/Helicopter combinations that the military has.

If it suffices for an attack helicopter, I'd say that the idea probably has serious potential for automobiles as well. I wouldn't expect to see it come to standard consumer cars yet, but for commercial drivers (particularly truck drivers who have massive blindspots) this could be invaluable. Imagine being able to see through the back of your box truck while backing up!