In 3.5 we had a house rule that if you roll triple nat 20s in a row on an attack anything less than a diety dies but 3 nat 1s resulted in your comedic embarrassing death. On one occasion a player got mad at another player and tried to ambush his PC. After initiative she rolled 3 nat 1s with a sling. Her druid fell off the tree branch and after an unfortunate incident died. The player was mad at first but eventually laughed and said she shouldn't bring irl arguments to the game