I have a bad habit of just not eating when I'm broke.
If you have an ironclad stomach, or are hungry enough, or desperate enough, here's another option (and keep in mind I personally have never done this and -never- will do it, but I know someone who has):
Animal food.
Some go for cat food. Or dog food. The guy I know ordered large primate feed online. It's obviously not intended for human consumption, but it'll keep you from starving. There are a few vitamins and minerals and such that they lack, which you'll need to take vitamins for. But, it's a super-cheap way to eat if you know the right stuff to get.
It's so disgusting to think of, and I don't think I could make myself do it unless it was the last source of food on Earth, but I figure hey, it's probably more nutritious and better for you than eating ramen.
Also this is mainly posted just to be funny, although it is true that some people eat animal food to save money. I really hope you don't, though, lol.