With the help of digital media and networking technologies, today's learners are increasingly participating in the consuming, producing, and disseminating of new meanings in various modes such as text, image, sound, video, or all together--particularly in online communities--forming new identities as knowledge producers. By using online ethnography coupled with qualitative data collection instruments including participant observation and e-mail interview, the study explored (a) how game players participated in learning how to make "mods" a fan-programmed game feature and (b) why they created and shared mods with others. Findings revealed that game players participated in learning through collaboration, appreciation and validation, and mentoring. Moreover, affiliation, offline interests, and increased enjoyment motivated them to participate in making and sharing mods with their peers. The findings also unveiled that gaming culture has been overlooked or neglected as a form of possible applications for informal online learning, which can provide many rewarding benefits--especially to teachers, researchers, and school reformers--with a new understanding toward today's learners' multiple identity formation.