I bring vegetable sandwiches to work. There are zillions of combinations. Try chedder, provolone, cucumber, sprouts, lettuce, tomato, olives....basically anything you would put in a salad.

Also, carrot salad is a fabulous sandwich topping. My co-workers were very impressed when I brought a turkey sandwich topped with carrot salad (the kind with the rasins and such). I almost had to fight to eat my lunch.