Frugal meal ideas thread
But in summary, bean & lentil soups are awesome and filling and are usually pretty cheap to make.
Edited to add: One cheap snack I like is to take some tinned (or cooked from dry) chickpeas, briefly sautee them in oil with a bit of cumin or curry powder, then roast them in the oven until they're slightly crunchy. Much more satisfying than just bread. :)