You can buy a mini hot glue gun at the dollar store for just a few bucks, so technically there are not to be a lot of situations where you need to know how to make a hot glue gun from scratch with a few simple supplies. But that doesn't make the fact that you can do so any less awesome.
This how-to video is definitely one of the coolest I have seen ever:
Watch it and you'll learn how you can transform a simple tin soda can into a functional hot glue gun with nothing more than a knife for cutting, a lighter, and a bit of tape (and of course the glue that goes inside). I am blown away not only by the simplicity of the method, but also how clearly it is presented in the video, and how well the glue gun actually works! Now that you have a cute little glue gun head over our 40 Borderline Genius Glue Gun Projects That Will Enchant Your Life and 50 Jaw-Dropping Ideas for Upcycling Tin Cans Into Beautiful Household Items!.
Tutorial by MrGear youtuber.