The document discusses the work of Joe McCarthy in hybrid computing, which mediates connections between people, places and things both online and offline. It summarizes three of McCarthy's projects that aimed to promote community: MusicFX helped democratize music selection at gyms, Proactive Displays enhanced connections at conferences, and C3 Collage increased sharing and relationships in workplaces. The document concludes by outlining some open challenges in hybrid computing regarding privacy, evaluation of systems in real-world settings, and mechanisms for situated serendipity.