Oh my...wow... https://www.youtube.com/watch?v=etm65A54ND8
Man! This guy is having too much fun!
Somehow, I doubt his methods are good for the AR lens coating, but he does get the job done...
Here is a direct link to the 3:15-mark, where he lights the fire.
Oh my...wow... https://www.youtube.com/watch?v=etm65A54ND8