You know that blur of movement on Christmas morning when children meet presents and presents meet children, scraps of wrapping paper fly into the air and float down, confetti-style, all over the living room? Five minutes later, the presents are all unwrapped, the children sit panting, and everyone wonders what to do next.
It does not happen in the Harford household. For the past few years we have had a rule: you cannot unwrap the next present until you have written a thank-you note for the last one.
More here – Tim Harford The Undercover Economist.