Hackathons have become a "thing". It seems like everyone is running one, sponsoring one or participating in one. Along with that popularity has come a fair amount of criticism of both the form and function of the hackathon event. Between Geeks Without Bounds and Random Hacks of Kindness, we've been involved with more humanitarian hackathons worldwide than almost any other entity, and as such we've developed some pretty strong opinions about what makes for a really successful hackathon. We'll explain why cash prizes are a bad thing, why (and how) you want to encourage existing projects to submit challenges to your event, and what you can do to make sure that the results of your hackathon don't disappear after all the pizza is gone.