MRE's are great to have. If you use the heaters in them for your food, you can use them as heat packs inside your shirt or for your hands. WARNING: They get extremely hot and the fumes are bad for you. I always kept water purifier tablets. Between boiling, tablets and knowing how collect water, you'll be set. A back up filter would be a good idea too. You can go longer without food than you can water so you'd better play it safe.