Subway/Fire House Subs/Which Wich: Choose the 6-inch Turkey Breast or Ham Sub on Wheat. Avoid the Mayo and try Spicy Mustard instead. Load it up with veges, and avoid any high-calorie sauces like ranch or oil and vinegar.
Opt for water or unsweetened tea (and don't add artificial sweetener!) instead of sodas and avoid the chips.
You can walk away with a pretty good lunch alternative and not feel guilty that you broke your diet. If you can - avoid the cheese too - but I can never leave that out!