Pat's has been a Tucson classic for longer than most of Tucson's residents have been around. Definitely not a spot for the weak-stomached, this tiny drive-in joint has been slopping onions, mustard and chili on hot dogs and hamburgers for more than 40 years. Speaking of greasy: The fresh-cut, skin-on fries are one of a kind, and patrons either love them or hate them—but no one can argue that there's a better deal for lunch. Just make sure you bring cash. Word to the wise: You'll need a large soda to cool the burn on the spicy stuff.