This is just great - Books and data and loads of information for free - that you can modify, add to and edit. Heard of Wiki ? (A wiki (pronounced "wicky", "weeky" or "wi-key") is a website (or other hypertext document collection) that gives users the ability to add content, as on an Internet forum, but also allows that content to be edited by other users.)
Here are some amazing things :
Wikipedia - An open-content encyclopedia
Wikibooks - Free textbooks and manuals
Wikisource - Free source documents
Here are some samples :
Data Encryption Standard - From Wikipedia, the free encyclopedia
Fractal - From Wikipedia, the free encyclopedia.
Theology - From WikiBooks
(The portion on Hindu Theology/Philosophy was added by Shamit Bagchi - neat right ?)
It says at the Wikibooks submission site :
Please note that all contributions to Wikibooks are considered to be released under the GNU Free Documentation License (see Wikibooks:Copyrights for details). If you don't want your writing to be edited mercilessly and redistributed at will, then don't submit it here.
You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource. DO NOT SUBMIT COPYRIGHTED WORK WITHOUT PERMISSION!