During the week I mostly eat: egg whites, beans, frozen veggies, fresh veggies, almonds and blueberries. Sometimes I make chicken stir-fry. On Saturdays I eat whatever, usually going out, or to a BBQ, or to a friend's house. On Sunday morning I usually go out to brunch and then the rest of the day it's back to the basic stuff listed above. During the winter I often make turkey or lentil Chili. Most of it is pretty cheap except for the almonds and blueberries. However, I'm just feeding myself so it's still not that expensive.

I used to eat anything and everything but I found that too many carbs and cheese made me get fat, and "crash." Most meat makes me feel sluggish. I'd eat more fish if I had more confidence in my ability to prepare it.

edit: I also have a banana for breakfast. very cheap at Trader Joe's.