This May or may not work. Let's hope it does, cause this is gonna be like a weird Mad Libs epidemic!
The idea is, you quote a person in a book, movie, television show, etc., and leave the last word out, or a few words scattered in between! Then when someone answers, they fill in the blacks with something ridiculous. Then whomever replies will leave their own quote to be completed, and so on.
First Person: May the ____ be with you!
Second Person: May the 'hamburgers' be with you!
(They leave their own quote): One ____ to rule them all.
Got it? And if you want to do a few missing words in a row, you do this: Do not _____ the ____ of the _____ _____!