One such game, called 'ghost', is now something that Stacie and I play. The way it works is difficult for me to explain, so please bear with me while I attempt it.
The object of the game is to spell a word, without spelling a word. One player starts the game by saying a letter. The next player then says another letter, and the whole letter-picking thing goes back and forth until one person has finished spelling a word. When that happens, the player who finished the word gets a letter of the word 'Ghost'. If a player gets all of the letters in the word 'Ghost', that player loses the game. Hrmm. That wasn't very clear, was it? Let's look at a game that's starting it's sixth round.
P1: "Okay, let's start with... 'Q'"
P2: "Aw, crap. Umm... I guess the only letter I can go with is 'U'"
P1: "Alright, 'I'"
P2: (thinking of the word 'quiet', which ends on P1) "'E'"
P2: "'S'?! What the crap kind of word starts with 'Quies'?"
P1: "Do you want to challenge?"
P2: "Grrr.... No, I know you have a word up your sleeve..."
P1: "Well, what's the next letter?"
P2: "Ah-ha! I know what word you're going for! 'C'"
P2: "Yes! I win this round!"
P1: "Huh? But we didn't finish the word!"
P2: "Yes, you did!"
P1: "But I was gonna make you finish off 'quiescence'!"
P2: "That's as may be, but 'quiesce' is a word. You get an 's'."
P1: "Crap! I guess I have 'ghos' against me, and you have 'gh'."
I hope that makes things a bit clearer. There's other things, like how a word has to be a minimum of four letters long, and how proper nouns are not permitted, but those can be changed to fit how you want to play. Also, about the 'challenge' mentioned partway through the example: if a player is convinced that the current letter string will not form a word, that person may challenge. The player being challenged then either admits that there is no word, thus losing the round and getting a letter, Or the player states the word, making the challenger lose the round.
I find it to be great fun, and an excellent way to pick up new words for your vocabulary. Here's a very short list of some of the words that Stacie and I spelled last night:
Grah. There's a whole bunch more, since we played like, five or six games of it, but I can't remember the specifics. It's a really fun game.