Here's a recipe from askmen.com
Tuna and Bell Pepper Pocket
3 (6-ounce) cans drained, solid white tuna (in water)
½ cup chopped bell peppers
¼ cup chopped celery
¼ cup sliced onions
8-12 lettuce leaves (preferably green)
2 medium-size sliced tomatoes (8-12 slices total)
3 tbsp. fat-free Italian dressing
1 tbsp. dried oregano
1 tbsp. black pepper
4 (6-inch) pita breads
Combine tuna, green peppers, celery and onions in a bowl. In another bowl, combine dressing, black pepper and oregano, pour it over the tuna mix and stir. Refrigerate for a few hours. When serving, put 2-3 tomato slices and 2-3 lettuce leaves in each pita bread. Add tuna mix to pitas. There's enough for 4 servings.