Researchers at the University of Dundee have developed Six Speaking Chairs, each of which embodies a different way of thinking about tone of voice. It is better to view the chairs as provocations than as prototypes in the conventional sense, because their most important role is to spark discussion rather than to test proposals. TTS is found in the screen-reading software used by many visually impaired people, in other eyes-free interfaces (such as Apple's iPod Shuffle), and in automated telephone answering services. Manufacturers of AAC (augmentative and alternative communication) devices are expecting speech technology to support this kind of emotional speech in the future. Social Mobiles inspired the format of the 'Six Speaking Chairs' as a design collection. A design collection, by which we mean a series of designs conceived to be considered collectively, can provoke more divergent discussion than more conventional design concepts.