This paper presents an exploration of user interfaces, persuasive interfaces and feedback techniques in the domain of the sink. Waterbot is a system to inform and motivate behavior at the sink for the purpose of increasing safety and functionality and ultimately motivating behavior change. Waterbot can be adapted to many current sink scenarios and demonstrates the breadth of interaction possible at the point of use of water. It functions as a platform for experimenting with safety, hygiene and water conservation in a sink. This paper presents the feedback and persuasion techniques of augmented physical interfaces with value-added design, automation, just-in-time prompts, positive and negative reinforcement, social validation and adaptive interfaces. Four design iterations are presented to affect behavior at the increasing cognitive levels of safety, functionality and behavior change. Author Keywords Context-Aware Computing, Persuasive Environments, Captology, Ubiquitous Computing, Wat...