I've searched almost all words associated with "Aerosol flamethrower" on instructables, yet I see nothing of the sort. Where I come from in England, they're very common, has anyone else ever made one and would the subject be to easy to make a whole instructable out of it. (even if other ways of using them were included?)
I've established it IS a bad idea, but also just to clarify:
~Spray~ can flamethrowers will NOT randomly blow up unless (to my knowledge)
You hold it the flame so it burn the nozzle.
You pierce the valve.
You douse it in <flammable liquid> and light or chuck it in a fire.