Thumbmaster (or Master of the Thumb) is normally played in conjunction with any other drinking game during the course of the evening.
How to Play
The game starts by choosing the person who will be the first Thumbmaster. At any time the Master chooses, they nonchalantly place their thumb on the edge of the table. Anyone who notices this must follow their example and place their thumb on the table. The last person to do this loses and has to drink, and becomes the new Thumbmaster. Anyone placing their thumb on the table at any other time must finish their drink.