In-N-Out. They've got some tasty fries and shakes. California only I believe, as I haven't seen them anywhere out of the state.
Five Guys Burgers and Fries. The best place ever.
Free unlimited toppings. The size of a large fries is a medium sized Mcdonald's cup full. Then they put it in your bag with the rest of your order, and fill the bag with fries. It blows every other fast food joint out of the water.