Astute comment by Rory Cellan-Jones.

Suddenly I realised why a book worked on the Kindle but a paper did not. For me, reading a book is an analogue experience – I start at page one and continue until I’ve finished. A newspaper, on the other hand, is more random, more interactive. I scan the sections and leap from one article to another, much as I do on the web. That’s what is already available to me – for free – on newspaper websites, so why would I pay for a less satisfactory digital newspaper? Newspapers have woken up rather late to the fact that they’ve been giving away content online which could be monetised through e-readers.

There are other reasons why the Kindle may not be quite the game-changer some are claiming. Is a device costing upwards of £200 really going to persuade many people to abandon paper for a screen – especially when you can get a netbook these days for around the same price? And there will be questions about Amazon's walled garden, which allows some other e-books to be read on the Kindle but doesn’t allow titles from its online store to be read on other devices. Other contenders – perhaps including an Apple tablet – may learn some lessons from Amazon and take digital reading to the next level.

The Kindle looks to me like an attractive but expensive niche product, giving a few techie bibliophiles the chance to take more books on holiday without incurring excess baggage charges. But will it force thousands of bookshops to close and transform the economics of struggling newspapers? Don't bet on it.

Last May, the Economist carried an interesting report (now hidden, alas, behind a paywall) about technology developed by a Cambridge company.

TOUCH screens, once the preserve of science museums and ticket machines, have become commonly available on mobile phones thanks largely to the popularity of Apple’s iPhone. Now a novel hand-held device has been developed that can turn an inert tabletop into an interactive touch-screen. It could even end up being projected from a mobile phone.

The device developed by Light Blue Optics, a company spun out from Cambridge University in England, embodies a tiny projector and sensors that allow it not only to cast an image onto a flat surface but also to detect when the image is being touched. This makes it possible to press buttons, move and manipulate virtual objects such as photos and navigate between different screens, all just by touching the projected image.

Today, there’s a piece in Technology Review which shows how Light Blue Optics is finding ingenious applications for the technology, like this:

The new projection device, developed by Light Blue Optics, based in Cambridge, UK, uses a technique called holographic projection that allows it to be far smaller than current in-car HUD systems. “We can make an HUD so small you can put it into a rearview mirror or wing mirror,” says Edward Buckley, Light Blue Optics’s head of business development.

Details of Light Blue Optics’s prototype were presented today at the Society for Information Display’s Vehicles and Photons 2009 symposium, in Dearborn, MI. The prototype projects an image through a two-way wing mirror so that it appears to be about 2.5 meters away, superimposed over the reflected road scene. The picture appears to originate from a point in space in front of the mirror, only from a narrow perspective.

Existing HUDs require relatively large liquid-crystal arrays and optics to generate an image, says Buckley. “In a BMW 5 Series, the size is about five litres,” he says. “We can make it about one-tenth of the size. This means you can start to put these virtual image displays where you couldn’t previously.”