I recall reading somewhere about there being late lunch deals in the financial district - half price sandwiches, etc., after 2:00pm or so.
As I generally eat a later lunch, seeing if anyone knows about such deals!
I can start with one I've come across - there's a buffet-style food-by-the-pound place near the corner of Pine and Battery called Chez Carla (Yelp profile: http://www.yelp.com/biz/4ODXuV9cSeX_V...). They also have sandwiches and soups (never tried). The normal price of the buffet items is around $6/lb, but they cut it in half after 2:00pm. Food is decent, especially at the price. They have a serviceable roast chicken, roasted garlic potatoes, green beans, a little salad bar, a few other things I'm forgetting, and usually a couple rotating hot dishes (a pasta, usually something vegetarian).
Nothing to go out of the way for, but a good standby if working in the area.