Keep these under-200-calorie snacks handy in your travels:
2 cups fat-free popcorn (or buy 100-calorie packs for microwaving) Single-serve instant oatmeal Whole-wheat crackers (reduced-fat Triscuits are good) Energy bars with less than 200 calories (Luna, Kashi, 100-calorie Balance) Whole-grain, ready-to-eat cereal (Oatmeal Squares, MultiGrain Cheerios) Sliced apple or celery sticks with 1 tablespoon peanut butter Snack-size light yogurt or fat-free pudding (4 to 6 ounces) Snack-size low-fat cottage cheese packs Single-serving size bag (about 1/4 cup) nuts (almonds, soy nuts, pistachios, walnuts) Any whole fruit Serving of soy chips Single stick of string cheese Fruit leathers, or flat strips of puréed dried fruit Single serving of dried fruit and nut mix
I disagree with the recommendation of low fat and light foods. These foods still have to taste good for people to buy them, so manufacturers simply replace fat with sugar and/or chemical sweeteners. Good fats are essential to health and provide satiety so you don't overeat or have binges.
Also, many of your recommendations include whole grains which are unfermented or unsprouted. Such grains simplyt break down into sugar and cause a whole host of health problems.
It's far more important to look at the source of the calories than counting them. If it wasn't, you'd be able to substitute one meal a day for a Twinkie and still shed pounds...