RoC77 wrote:If you can get your hands on the military versions(which are better) you'll have 24 meals to choose from. If you eat them 3 times a day you'll get sick of them fast and get fat. But there's enough calories in one to last you all day if you're not that active, so that could strech out longer.
When I was doing Wilderness Survival merit badge in Boy Scouts we had some guy buy us a bunch of these, the summer and winter versions. If I remember correctly the winter meal had something like 5000 calories in it. I was a fat little kid and I ate the whole thing in one sitting. There was this giant energy bar that was filled with butter and all kinds of other gross things. It was a pretty awesome meal, I guess.
I also remember there are some packages where you pull a string and it cooks a stew inside itself in a few minutes and you can tear it open and eat.
Honestly I think the cheapest way to eat is just to learn how to cook, you can always buy vegetables cheap and cook them up however you want. Pizza is also insanely cheap if you make it yourself (and it's SO easy).
Also if the world does end everyone will want to hang out with you cause you can cook them better food than they could scrounge up themselves.