Massachusetts: Boston Burger Co.
The shop: Boston Burger Co. in Boston, MA
The milkshake to order: Cereal Killer
The Boston Burger Co.'s specialty shakes, coined as "Freak Frappes," are piled high with treats like cake, doughnuts, bacon, and toasted marshmallows. Try the Cereal Killer, which comes sprinkled with Fruity Pebbles cereal and a Rice Krispies treat.