A third fascinating use case for Bitcoin is micropayments, or ultrasmall payments. Micropayments have never been feasible, despite 20 years of attempts, because it is not cost effective to run small payments (think $1 and below, down to pennies or fractions of a penny) through the existing credit/debit and banking systems. The fee structure of those systems makes that nonviable.
All of a sudden, with Bitcoin, that’s trivially easy. Bitcoins have the nifty property of infinite divisibility: currently down to eight decimal places after the dot, but more in the future. So you can specify an arbitrarily small amount of money, like a thousandth of a penny, and send it to anyone in the world for free or near-free.