This is a great DIY project for anyone who wants to start blacksmithing on the cheap. Great for SHTF situations to fix knives or even make them. This is an inexpensive tabletop forge out of a soup can (any can really) with a plaster lining.
The forge runs off of a common propane torch (spiral flame will work better than pencil flame) that can be bought at any hardware store. I have a friend who likes to tinker with blacksmithing and he made one of these years ago, he still has it and still uses it!
My brother made something similar to this out of an old coffee can, so it was huge. He has made knives from old railroad stakes using his.