A leyden jar is generally just a basic house made capacitor. We’ve shown you exactly how to make them before. This, however, is exactly how you make a ridiculously big one. [Nickademuss] utilized a five gallon container to make his leyden jar. That’s five whole gallons of lightning. The video, which you can see after the break, shows it illuminate the entire space when it lets out a relatively formidable spark. This is hazardous folks, be careful.