If you don't keep a fire extinguisher in your car, you should. Its actually mandatory in some European countries. I was lucky enough to put my hands on a OE mount for my car that places the extinuisher right under the front of the drivers seat (reachable while belted in the seat).

A family member of mine witnessed a bus roll-over on an interstate in PA several weeks ago. The engine compartment caught fire and proceeded toward the passenger compartment. He was able to keep the flames at bay with a 5 lb. ABC while two other good samaritans pulled the injured driver to safety. Without the extinguisher, the driver would not be around today.

Several good points have been made:

(1) Mount the extinguisher with metal (not plastic) hardware. It could become a ballistic missle in the passenger compartment. You could put it in the trunk, but accessibility is important.

(2) Get a good quality extinguisher - I stay away from plastic hardware like you find at the local Wal-Mart. Pay a little more for professional grade equipment from an authorized dealer (Amerex and Badger) and you won't find the pressure has leaked out and its useless.

(3) Inspect the extinuisher on a regular basis. Make sure the pressure to spec.

(4) The extinguishing agent in an ABC extiguisher is caustic to plastic, vinyl, and leather. If you do use one inside a vehicle, clean up the powder as quickly as possible. If you are concerned about damage, you may want to consider a CO2 or halotron extinguisher. If you do, keep in mind that extinuishing agent is not as effective as the ABC powder.

Best wishes.

Craig.