In this paper we present SpectroFlexia, a form of interactive stained glass that is designed to present information in the periphery of people's attention. SpectroFlexia is developed in an iterative design process which revealed a low-cost method of smoothly changing the color of light shining through translucent materials. Using this method, SpectroFlexia can display several types of digital information through the speed at which its colors change. In addition to providing peripheral information, SpectroFlexia is designed to serve a decorative function. An informal user exploration with an interactive prototype of SpectroFlexia indicated that smooth color transitions are a promising way of presenting peripheral information.