The Internet can be used to reconfigure access to information and people in ways that can support networked individuals and enhance their relative communicative power vis-à-vis other individuals and institutions, such as by supporting collective action, sourcing of information, and whistle blowing. The societal and political significance of the Internet is a matter of academic debate, with some studies suggesting a powerful role in creating a “Fifth Estate,” and other studies challenging such claims. Research on this issue has not yet comprehensively focused on social network sites and those operating in a very liberal-democratic context. Based on an embedded case study of Facebook use in Finland, this study focuses on the uses of social media in building communicative power, such as in capacity to foster social movements in ways that conform to conceptions of the Internet’s Fifth Estate. The case study combines qualitative and quantitative methods to examine a sample of 2,300 Facebook pages and their online and offline activities and impact qualities. The results located 27 pages that reached a threshold we established for identifying online social movements with the potential for enhancing their communicative power, with a small minority of four cases appearing to have actualized communicative power. These findings not only reinforce the potential of Fifth Estate activity on social media but also underline the challenges of societal change in this predominantly entertainment-oriented social context. In addition, the study showcases the intertwined process of online and offline attributes affecting societal influence of online social movements.