There’s a scene a few chapters into the comedy science-fiction novel, The Restaurant at the End of the Universe, where Zaphod Beeblebrox, the two-headed former president of the galaxy, is in a spot of trouble. A few moments earlier, he had been standing on the bridge of a starship, now he suddenly found himself mysteriously teleported to a café on the strange, alien planet of Ursa Minor Beta. Puzzled at what has just happened, Zaphod instinctively reached into his pocket for his sunglasses:
[He] felt much more comfortable with them on. They were a double pair of Joo Janta Super-Chromatic Peril Sensitive Sunglasses, which had been specially designed to help people develop a relaxed attitude to danger. At the first hint of trouble they turn totally black and thus prevent you from seeing anything that might alarm you.[1]
What was science-fiction in 1980 when Douglas Adams wrote this passage has become reality in the twenty-first century. Augmented reality, to be precise, the new buzzword in computing. Augmented reality is a technology that allows computer-driven data to overlay your view of the real world. Originally developed for military applications (for example, projecting flight information onto the visor of a fighter jet pilot), augmented reality is now breaking in to the world of consumer gadgetry.