Ubiquitous computing aspires to support human activity seamlessly with interactive technologies. This involves the proliferation of digital devices of different form and function in our environments, and the appropriation of diverse sensing modalities to observe activity, capture context, and provide natural interfaces to users. In this talk I will propose eye movement as a modality for ubiquitous computing, as the eyes are where the action is. While eye tracking has been long established for diagnosis and gaze control in human-computer interaction, I will argue that eye movement can be leveraged in novel and advanced ways, both as source of contextual information about users, including their health and well-being, and as a channel for communication and interaction. I will illustrate this with examples that explore eye movement analysis for activity recognition, the use of smooth pursuit eye movement for calibration and interaction, and the multimodal combination of gaze and touch. I will close with an outlook toward serious application of eye movement for health monitoring.