After seeing Mark K's unfortunate experience with a fire in his cnc laser during a cut with acrylic and the aftermath of the fire extinguisher, I started to look into some fire extinguishers. I have a dry chemical extinguisher, but I think this is not a good choise for a cnc laser system because it is very corrosive and will damag any electronics and exposed metals. If you want to have a chance of rebuilding the system after an event like this, it may be best to have a different extinguisher on hand. Other extinguishers are really quite expensive and relatively indiscriminate with regards to localization. I found a new product that could be better. It's called the tundra fire spray. If the fire is small and hasen't engulfed the whole laser system, it may be better than a regular extinguisher as in Mark K's case (forgive me if I am misjudging the situation, I wasn't there to see anything). Further, the cost is only around $14. A halon extinguisher runs in the hundreds. I have a cheap (but effective) dry chemical extinguisher as backup, but this may save the laser system from serious damage.