My idea seems like an easy one Ben can knock out in one episode easily. My idea is to build a charging iphone or other phone case, like a Mophie, but include 2 batteries which can be switched to with a switch. One battery can be charged with a normal charger and one with piezoelectric strips so that every time a vibration happens on your phone, the battery is charged. I've drawn this up multiple times but don't know how to execute. Thank you in advanced!