5. Ramen Cup of Soup
The Ramen cup-of-soup is a simple, if not entirely healthy, meal option for travelers. Just ask for hot water when the drink cart comes 'round and voila--lunch or dinner is served. Make sure you bring a fork or spoon, especially on short flights where in-flight meals are not served, because the flight crew may not have utensils to offer you. I like to bring my own camp utensils, or you can grab plastic utensils from a fast-food joint in the airport.
4. Granola and Fruit
I buy milk at the airport, or yogurt if I can find it, and assemble a breakfast bowl on the plane. I use my own collapsible camp bowl and camp spoon, but you can ask any fast food place at the airport for an empty cup and plastic spoon before boarding the plane. If you don't want to mess around with milk or yogurt, another alternative is to substitute a string cheese stick. Dried or fresh fruit works, and I bring as much as I can carry.