[mrevelle]

Balance (protein, carbs, vitamins) and variety. To save money (and keep the girlish figure) eat half of large-portioned dinners and have the leftovers for lunch the next day.

Coffee in the morning, sometimes in the afternoon, just to get revved up. A liberal nap-taking policy, because sleep is the best cure for fatigue. Exercise and sunlight, go running/cycling/tree-climbing outdoors for efficiency.

And oatmeal! Plain old oatmeal is cheap, healthy, and filling. Try it with bananas or blueberries.

[SwellJoe]

I'm also a big fan of oatmeal with some fresh fruit or raisins/craisins, some crushed walnuts or almonds (raw, not smoked or roasted, as any kind of cooking breaks down the healthy fats in tree nuts), and a little brown sugar usually makes for a nice solid day of pleasant work.