This seems to be a 12V DC carbon arc lamp. Rather nice idea in some ways, but carbon arc lights give off significant UV light. It probably burns little bits of your retina to look directly at this light. Also, it may get hot enough to use as a small welder. Here is a link to a short page on carbon arcs.

I agree with the consensus that a flashlight or LED light is a good thing to carry with you or have stored in your car. Since I typically carry a PDA and a cell phone, I have semi-reasonable lighting available to me all the time. I think it is better to be reasonably prepared for foreseeable emergencies (is it really spelled like that?). A solution like this one is rather like "how to make an emergency jack out of a pair of shoes and the springs from your back seat". Better still to keep a jack in the trunk.

That being said, I recall the scene in "The African Queen" in which Humphrey Bogart and Katherine Hepburn use a charcoal forge to repair the propeller for their boat. A carbon arc welder might have been handy right then.