"Kindle" is Amazon's e-book reader. Its making lot of news these days. Amazon recently slashed the price of the device to $259. e-books can be downloaded over GPRS/3G/wi-fi networks and cost of each e-books is fairly valued. Users need not pay for the wireless charges, they only pay for the downloaded books. The latest version of kindle is supported in many countries. The features supported in countries other than US are a bit limited. It seems that there are some charges for wireless connectivity in other countries. Wireless transfer of e-books is not mandatory as they can be transfered from USB also.
The content in the kindle is believed to have strong DRM protection. In other words, its belived that the content downloaded by paying the price once, cannot be shared with other people. Amazon distributes the e-books in its proprietry format wth .azw extention. It has DRM protection which is tied to security key of the kindle hardware.
But this is not deterring the hackers. Two independent hackers are able to crack the code. So, one can convert the content of the e-book into a PDF file and can share it. Please be warned that its illegal and will be considered piracy. Converting to a PDF and keeping it for your own use should be OK, but I am not 100% sure. These two hackers go with the screen names "Labba" and "I [heart] cabbages".
"Unswindle" is a program developed by "I [heart] cabbages" which can convert the contents of the ebook into different movable format. Here is the link to his blog wich talks about this tool.
Sources:
http://www.crn.com/security/222100097;jsessionid=KC1EOI3I43IM1QE1GHOSKHWATMY32JVN
http://www.zdnetasia.com/news/security/0,39044215,62060167,00.htm?scid=rss_z_nw
