Our increasingly smart environments will sense, track and model users and provide them with personalized services. We can already embed computers in everyday objects such as shirt buttons and pencils; objects of all sizes, from wristwatches to billboards, will soon incorporate high-quality flexible displays; we have improved access to wireless Internet communication; and we are now transitioning from traditional linear to targeted interactive media. The convergence of these factors -- miniaturization, display technologies, wireless communication, and interactive media -- will allow us to...