I learned that steel wool burns years ago while grinding with a pack of steel wool on the workbench. A buddy of mine did the same thing with a coffee can partially filled with black powder.
Making a fire by shorting a battery is good to know
but a book of matches is sooooo much easier and cheaper, don’t leave home without them.
I once saw an uncle create a short with his watch band while working on a tractor. That was comedy gold.