One common mechanism in games of all sorts is "Collecting Letters."

You have some word, that you're spelling out, and there are letters to the word that are collected. Then there is either a positive or negative reward.

In many pinball games, you have to hit each of a sequence of letters, spelling some word in the theme of the game. You get some sort of reward when you get them all.

In video games, a level frequently features the letters of a word, hidden in various places. You collect all the letters, and get some sort of reward.

In "Horse," a game played with basketball equipment, players take turns throwing hoops. For each successful throw, you get a letter: "H", "O", "R", "S", or "E". You can only get them in sequence, though, so it's not really about collecting letters.

Related but Different: HangMan?, BasketBall?, and the WheelOfFortune?, all of which prominantly feature letters.

(Yes, I realize this is something of an odd observation.) -- LionKimbro