My brother and I and some of our other friends at Rice (Robo, Baseman, Kylec) made up a game called the Mizoovie Game Part II that we used to play all the time. It goes like this: One player names two movies, and the other players try to name a third movie that includes an actor from each. For example, if I say Star Wars and Ghost, the answer is Soap Dish (Carrie Fisher + Whoopi Goldberg). There may be other answers, but you have to have something in mind from the beginning; you can't just throw out two random movies as there may not be a solution.
This is a great car game. It works best when you know the other players have seen a lot of the same movies as you, and if you use movies with ensemble casts, because there are more possible permutations. (If you use movies that only have two significant roles each, there are only four possible combinations.)
I taught you a game! Here are a few more:
Stand By Me & Ghostbusters
Face/Off & Heathers
True Romance & The Day of the Locust
No cheating and using IMDB!