This case study is based on ethnographic work I carried out on a free and open source software project. My observation and participation as a user of the software informed the work that was central to the case, as did my online observation. I also analyzed a series of interviews of software developers that had been conducted by a member of the software project, which were published on the project's website. My work combined online ethnography with traditional participant observation. There is a great deal written on the methodologies of both online ethnography and participant observation: what is distinctive about this case study is that it shows how to use both approaches. The case study stresses specific steps, ranging from formulating research questions, through data gathering online and in person, and analysis and writing up. The case study offers advice on software tools that are helpful for mixed-mode online/in-person ethnography.