Demo of the application is http://apps.facebook.com/riddlesforme It is monetized via offerpal and banner adds. It comes with over 200 questions already installed to get you started. If a user gets stuck they can cheat and skip the questions - to cheat they must complete an offer and hence you earn money when a user is stuck. It has a help forum where users can interact and discuss hints and tips for the riddles. It has ads top bottom and middle which are very easy to edit. Within one week we made $24 just off the "Stuck on Question" element.