The author contributes new insights into everyday literacies in participatory cultures using a multimodal analysis of three LGBTQ+ reaction videos on YouTube. LGBTQ+ reaction videos respond, often comedically, to oppressive media forms and technologies. In the analysis, the author considers how reaction video makers draw on seven meaning-making modes and multimodal techniques in digital composition to enact practices of critical media literacy, namely, to identify, interrogate, and disrupt dominant ideologies that undergird media forms and technologies. Through analytic video logging and multimodal analysis of video episodes, the author also examines the role of humor in enactments of these practices. The article forwards the conceptual framework of humor as political possibility made manifest in the range of ways that video makers construct slips of humor, compose multimodal parodies, and create satires that critique dominant ideologies and imagine new ways of being in the world. Examining literate activities in participatory cultures with a focus on LGBTQ+ identities has purchase to explicate possibilities to name, challenge, and transform dominant ideologies toward more just futures.