Very fun way to review for a test or quiz.
With "I Have, Who Has?", each student gets a card. You pick a student to start it off. For example, a card may say, "I have Christopher Columbus, who has a line dividing the New World between Spain and Portugal?" The student who has the card stating "I have the Treaty of Tordesillas" will read their card, and on it goes. Finally the last card will meet with whichever you started with.
Cards work best printed on colored cardstock. Also, it's fun to time students to see if they can beat their original time or compete with other classes.