Ambient display research is a new but burgeoning field studying the design and evaluation of systems that provide non-critical information to the periphery of human attention . Different displays receive their input from different sources and display output in a variety of ways. However, as little middleware exists to support ambient display development, developers must rewrite from scratch code used to translate input to output. To correct this problem, we are designing, implementing and evaluating an ambient display toolkit. We approach this problem by first outlining the design space of ambient displays, classifying several previously built displays by input and output type. We then look at code used in those displays to determine additional patterns. Next, we develop an architecture and a library of functions to support these patterns. As a final step, we rebuild a few existing ambient displays using the toolkit to evaluate its effectiveness and then iterate the toolkit design based on our findings.