I work and usually eat breakfast at my desk. I keep a big tub of oatmeal (quick or regular) in my drawer with raisins. I just get hot water and make it. You could also keep nuts, applesauce, brown sugar, maple syrup or cinnamon to make it more interesting. I use a 1/4 cup measure as a scoop so that I know how much I am making.
I also pour frozen fruit into a container before I leave the house and top it with plain yogurt. By the time I eat it mid-morning the fruit has melted and it makes a good sauce for the yogurt. It also keeps the yogurt cold.