I remember reading somewhere that you can burn more calories while you are asleep than by watching TV. There are many effortless ways of burning calories like, laughing, kissing, drinking more water and chewing gum. But in terms of total body rest, it is proved that when you are asleep you burn calories.
Apparently, the average person burns about 77 calories an hour while sleeping, but the actual number of calories burned by a specific individual depends on his or her Basal Metabolic Rate. The Basal Metabolic Rate (BMR) is the minimum rate at which your body burns calories when at rest. The older you get, the lower the BMR. There are various ways to increase the amount of calories burnt during sleep, for example, by turning down the heater, avoiding eating carbohydrates for at least six hours before going to bed and drinking green tea just before you sleep. In case of watching TV you burn only 56 calories per hour and also increase your appetite by watching ads of different edibles.
But if burning calories without putting in some serious effort is your way of life the best thing to do is to read a book while sitting on a chair because it burns 100 calories per hour. Still, these are standardized calculations and may not be true for every person because the burning of calories per hour depends upon many things including body mass and your basal metabolic rate.