Original Burger

Who makes it: Louis' Lunch
Where it can be found: New Haven
What it costs: $4.50

What makes it innovative: Depending on whom you ask, hamburger lore has it that Louis' Lunch served up the original burger in the U.S. The restaurant still makes its hamburger as it did in 1900, putting a beef patty and tomato, onion, and cheese between two slices of white bread. Ketchup and mustard are still off-limits.