Making twenty cups of tea from one tea bag. When you repeatedly fill your tea cup with hot water with the same tea bag. It is essentially extremely dilute tea brewed based on the principles of homeopathy.
Flatmate 1: It's snowing and there is only one tea bag left in this house
Flatmate 2: That must be mine since you 've all had tea!
Flatmate 3: Relax, one tea bag is enough for all of us. Let's try homeopatea!