One of the great things about being part of the community of Moodle users (that numbered 50 million last time I checked) is the wealth of third-party add-ons available. One module I think is great is the Game module. It takes any normal quiz, glossary or questions and turns it automatically into any one of 8 games, from hangman to sudoku to something similar to 'who wants to be a millionaire'. One of my great tricks is to get students to build a glossary of key words and definitions for a topic as we go. With the quiz module, you can then turn that student-developed resource into a game that everyone can play: it's like the students build their own interactive learning tools.