Forget going to college for Engineering, you yuppie. According to our research, the fastest way to build something that might make a difference, or at least your life a little easier, is to go to prison. And, face it, getting into prison is a lot easier than paying back your student loans. Plus, getting a job is just as hard after graduation as being an ex-con anyway.
To make the infamous prison lighter, all you need is a battery (Orange is the New Black shows an AA, but any battery will work really) and some gum wrapper or foil from a cigarette pack. Attach one end of the wrapper to the negative side of the battery, and then just connect the other end to the positive. Bam! It's the easy to light a cigarette, become an arsonist, or simply start a camp fire in a pinch with your flashlight batteries.
Sure, it'd also be a cool bar trick, but then you'd have to carry around a battery and people would be like, "So, you just carry a spare battery around or do you always do this to impress people?"