Media façades and digital billboards are becoming an increasingly common fixture in urban landscapes. However, these contemporary signage solutions bear a number of negative social and environmental effects. In addition to obscuring historic architecture and increasing light pollution, they also compete with municipal signage, traditional advertisements, and mobile media to increase our experience of information overload. Smart (environmentally responsive) materials represent an ambient, low-energy alternative to contemporary digital signage. Although smart materials are being used as a sustainable alternative in engineering, they are less frequently used as a form of visual communication in urban informatics. This article describes three artistic experiments that reveal how smart materials can be used to convey information in urban settings.