As computers shrink, many professionals will wear an interface to critical informationThe trend toward miniaturisation in computers is continuing. The desktop became the laptop then the palmtop and soon, computers will disappear into a pocket, a piece of jewellery or a clothing label. Once the computer disappears from view, the next challenge will be accessing the information contained within, and the current odds-on favourite for these duties is the head-up or head-mounted display. The World leader in head-up displays - Microvision - already has units used in a range of applications, but the market was given a boost in January when Xybernaut unveiled the world's first commercially-available wearable computer, a product it describes as "a personal optical mobile assistant." The poma (pictured above) delivers instant access to email, the internet ... your entire PC. What separates the poma from those which have come before it is the VGA Liquid Crystal Head Mount Display, which enables the wearer to go about everyday business whilst being able to view the computer via an image superimposed over one eye. The concept is not a new one - fighter pilots have been using them for decades, surgeons have been using them over recent years and car makers have been experimenting too - all for situations where extra visual information is necessary but primary vision is critical and cannot be obscured. Using the poma is accomplished via an Optical Pointing Device (pictured), so it's mainly an information-retrieval system while you're on the go, though a wrist-worn keyboard is listed as an option. There will be a number of accessories available, including a metal carrying case, rechargeable battery packs, a carrying pouch and a 1GB external microdrive. The poma will go on sale later this month (March) and will cost US$1,499 direct from www.xybernaut.comAll before your eyesSurgeons in the United States have been using head-mounted displays during operations to monitor a range of vital information sources. The examples above, provided by Microvision (www.mvis.com) illustrate the surgeon's view with the information overlayed as he would see it.For further reading on this subject, we have provided a long list of links below, which will lead to further lists. Wearable computers are definitely going to play a role in our future and they won't be a fad, and they won't be one of those buzzwords which readily disappears - at least not until they have become ubiquitous.If you would like to read some extensive, well-written and well-illustrated articles on this subject, we'd like to select two which fit the bill perfectly. They're both from one of our favourite magazines - Popular Science. The first is about wearable computers and the second is about augmented reality.