I made a slightly nicer version of my prototype fire piston at work last night. It doesn't work as miraculously as the ones you can watch on youtube but it works. I would consider it more of a toy than a "forever fire starter" because it relies on an O ring and a way/materials to make char cloth. As evidenced by it early usage you could make a packing out of a lot of things and a lot of different material could be turned into char material. Me? I have enough ferrocerium rods to last me until long after I'm dust. It was still a fun project and I may try a few different versions I have swimming around in my grey matter. Definitely baffles the thought challenged people who see it in action though, it's worth it to make one just to see peoples reactions.