Re: An injection moulded magnesium chassis?
A standard Bic lighter will burn at somewhere between 420C and 800C. A windproof or "jet" lighter will go to a thousand-and-odd with the maximum temperature of a butane flame being about 1970C.
So instead of some nasty bastard putting a ciggy mark or a hole in your laptop, they get to cause a metal fire that will practically burn itself through the floor. That's if the battery doesn't explode on you. If Microsoft ever get to make enough units for the miniscule chance of a battery failure to rear its head and go "oh hai statistics", you're going to end up with a hell of a lot more than some warped plastic and and a nasty smell.
Incidentally, magnesium flames are rather blindingly brilliant.