Old ammo cans are the Tupperware of the emergency preparedness world. Although they were originally intended to carry loose ammunition or machine gun belts, we’ve seen these inexpensive stamped steel boxes repurposed to contain everything from tools and camp cooking utensils to fishing tackle, portable radios, and medical gear. Some DIYers even outfit them with batteries and USB ports to function as a portable charging station, or with speakers to serve as a boombox.