Your car breaking down in the middle of the road in the cold winter means no heater. Emergency blankets – you probably know them as “space blankets” – don’t cost much. Stack the car with a few – at least one per passenger. Add a sleeping bag if you have space. Bring wool blankets, which are even warmer, as an alternative. They are best for moist conditions. It’s a good idea to have chemical heat packs to put under the blanket.