Mbeach said it best. Get a good one of those little extinguishers for your vehicle. Much cheaper than having this happen.

I once watched an unattended parked car that was not running start doing that once while I was sitting in the line at McDonald's. My parents' Saturn wagon had smoke coming out of the dash recently and they had to replace some kind of switch. Luckily, it didn't light up like a box of matches like that VW did.

And they had 40K in that VW? Sure doesn't show.