Unacceptable: punching your little brother in the arm. Acceptable: doing it under the guise of a “game.” Did you play any of these kids’ games?

Doorknob! 

When someone farts, he or she must immediately say “Safety!” If a non-farter detects the fart and says “Doorknob!” before the farter says “Safety,” the person who says “Doorknob” gets to punch the farter in the arm. The farter can avoid getting punched if he or she touches a doorknob. But what if there are no doorknobs handy? In such situations (camping or swimming, for example), a substitute must be agreed upon before the first fart.

Jinx!

When two people say the same thing at the same time, the first person who shouts “Jinx!” wins. The loser is not allowed to speak until someone says his or her name. The penalty for violating the jinx rule is a punch in the arm.
Coke Variation: The first one to yell “Jinx! You owe me a Coke!” wins. The loser must then buy the winner a soft drink.
Caveat: It is often quite difficult to actually collect the drink.

Shotgun!

Who gets to ride in the most coveted position in the car—the front passenger seat, commonly known as “riding shotgun”? The person who yells “Shotgun!” first. But there are rules. To be awarded the front seat, everyone who will be riding in the car must be able to see it before someone yells “Shotgun!” If it’s yelled at any time before that, the “Shotgun!” is null and void.

Slug Bug!

(a.k.a. Punch Buggy) Played while riding in a car, the first person who sees a Volkswagen Beetle and yells “Slug Bug!” gets to hit someone in the arm. If it’s a convertible, two hits are awarded.
Variation: A “Pediddle” is a car with only one working headlight. Whoever spots one and yells “Pediddle!” gets to hit someone. If the Pediddle is a Slug Bug, they get two hits. If the Pediddle is a convertible Slug Bug (rare but not unheard of), then they get to beat the stuffing out of whoever else is riding in the back seat.