This book has iconic status with OBC:
In the late 1950's, there were two main types of flipping in my neighborhood:
(1) Pitching cards towards a wall, closest takes all. We called this lagging. This is where a lot of dinged corners comes from.
(2) Two players flip a card and let it land on the ground. One of them calls "odd"
or "even". If correct, the caller wins both cards, otherwise the other person wins. "Even" means both cards land face up or face down. "Odd"means one card lands face up and the other face down.
(1) was for multi-player competition. (2) was the default when there were only two players.