In the right hands anything can be used as a dangerous weapon. And in this case the anything is a container of corn starch, and the right hands belong to Ivan Owen, who used a leaf blower, an acetylene torch, and a flour sifter to turn the innocuous pantry staple into flamethrower fuel.
There are also a handful of custom-designed 3D-printed parts that went into this flamethrower's creation, so even if you wanted to build one yourself (which you shouldn't) you're going to have a hard time without Ivan sharing the schematics and models -- and that's definitely a very good thing. If you want to ring in the new year in style, stick to sparklers. [YouTube via Laughing Squid]