Free Mars Bar
Use code X7VMNG when you register with the Pitstop app and you'll have enough points for a free Mars bar at a WH Smith in a Roadchef location. While you're at it you can also claim a free Hash Brown at a LEON and a free set of Spring Rolls and a Chozen Noodle. Note they all have to be in a Roadchef location which are at 31 different locations on the roads around the country.