Materials: Brain, mouth.
Directions: Students take turns trying to think of something that they have never done, but which everyone else has done. As a teacher in Taiwan, I often give the example of, "I've never spoken Chinese to my parents." because I am the only person in the class for which this statement is true. This is a great game to introduce after you teach the present perfect tense (I have gone..., I have eaten..., I have never been..., etc.)
There are many ways to score this game:
1. Each person says an "I've never. . . ." statement, and whoever has never done that thing gets one point. (This encourages creativity while making the game easier and faster-moving.)
2. Each person says an "I've never. . . ." statement, and he/she receives one point (or candy or whatever) ONLY if he/she is the only person for whom this statement is true. (This is harder, as it can be really difficult for some of them to think of something that ONLY THEY have never done, especially if there are many students in the class.)
3. Think of your own way!
I often use this as a class starter - I bring 10 pieces to chocolate to class, and whoever can name something that ONLY THEY have never done gets one piece. For more advanced classes, you can be a grammar stickler and only award points / chocolate if they say the correct past participle (for example, "I've never gone..." instead of "I've never go...").