When you buy a printed book, you usually don’t expect to see advertisements, aside from those for other books. (Well, except in a famous episode of sitcom Hancock’s Half Hour.) But that’s exactly what you’ll find in the cheapest Kindle to date.

Amazon’s latest twist on the e-Reader is the Kindle with Special Offers. It’s the same hardware as the standard Kindle, but with the addition of screensavers promoting special offers from commercial partners. The screensavers will be specially designed to suit the electronic ink display. The details of all the offers can also be accessed through a link on the homescreen.

In return for choosing a model that allows this advertising, the buyer only pays $114 for the device, a $25 discount on the standard price. Normally I’d say that’s not really enough of an incentive, but things may be different with a device such as the Kindle where there’s no price competition among retailers.

Among the initial details will be a $20 Amazon gift card for $10 or a full-length album from the Amazon MP3 store for a dollar. But there will also be plenty of external advertisers, with Olay and Visa already on board.

In an attempt to make the promotions more tolerable to users and more effective for advertisements, Amazon is launching a Kindle app (mirrored on a website) allowing users to look at a series of pairs of potential advertisers and vote for the one they prefer. Companies will have to “win” a set proportion of such comparisons to be allowed to appear on a screensaver. The system is titled AdMash, which may be a nod to FaceMash, the forerunner to Facebook which ran a similar system comparing female students at Harvard.

Users will also be allowed to set personal preferences for the screensavers that appear on their device. However, they won’t be allowed to pick particular companies, but to rather decide on the themes of the screensavers, for example favoring ads that contain pictures of landscapes over those depicting people.

Even though the advertising concept has potential, I suspect it will be some time before it’s clear if it can work in practice. Firstly, the take-up is inevitably going to start off slowly as potential buyers usually wait until enough people have bought the new model and reported back on how disruptive or inconspicuous the promotional material is.

Secondly, the pricing suggests this may be an initial experiment to see if the concept takes with users. If it does, I would be amazed if Amazon doesn’t follow up by making the ad-supported version drop to the $99 price point.