Since 1998, I've been experimenting with the use of role-playing games to teach astronomy. Students play the role of competing teams of researchers, racing to solve some astrophysical mystery. In this article, I review what has been learned from using these games around the world over the last eight years. The most common problem encountered is a tendency for students to become overly political. An unexpected benefit of these games is the boost that they give to student self-confidence. Overall, they seem to work well with a wide range of students, ranging from ninth grade to graduate school, and students exposed to this game comment repeatedly on how the games changed their attitudes toward the scientific process. (Contains 1 online resource.)