How do people motivate each other to participate in a peer production environment? This question is addressed through the study of user-initiated contests on the electronically mediated social network that surrounds the programming language Scratch. The users of Scratch, mainly youths, have created their own mechanisms to motivate and recognize creative achievement. Some wish to achieve popularity on the site by having their project posted on the front page so contest creators offer to perform actions that will help participants reach that goal. Other contest creators, though, offer hand-made, personalized gifts such as drawings and animations made to spec. For those who offer both incentives, the ad hoc, personalized rewards are deemed more valuable than the mechanisms provided by the web site. Users are appropriating the technology, establishing their own organizational structures that encourage creativity.