The Reader devices, which store 160 books and are smaller than a hardback printed book, are available for online pre-order from Sony and Waterstone's, and will hit stores in September.

Each device will cost £199 – half the price of the Iliad reader device currently sold through Borders – and will support a range of file formats, as well as ebooks.

"Reader allows people on the go to carry a wide variety of reading materials whether they are on a flight, in a waiting room, or outdoors," said Steve Dowdle, managing director at Sony UK.

The key idea behind the devices is that they sport an e-paper display – in the case of Sony, the display has been developed by E-Ink – which doesn't need backlight and so offers the same reading experience as the printed page.

However, the phenomenon has polarised debate over print and screen, and even authors, to whom this represents a potential additional revenue stream, cannot decide which side of the fence they are on.

"The great thing about electronic books is that in the long run they will benefit writers, creating an easier way to enable first-time authors to get their work in front of the public. That will be a revolutionary change," said author and ambassador of the Reader, Toby Young.

However, the better-known Nick Hornby wrote in his blog recently that "attempting to sell people something for £400 that merely enables them to read something that they won't buy at one hundredth of the price seems to me a thankless task".

Do you think e-reader devices will do anything more than scratch at the dominion of the printed book? Leave your comment below.