The Scheme Programming Language

The Scheme Programming Language - fourth edition

Available for free here
Or you can order the paperback version on Amazon: The Scheme Programming Language, 4th Edition

Queuing Theory Books

A large list of online Queuing Theory books can be found here.

Dietary Guidelines for Americans 2010

Good to read before you go shopping.

Download from here.

Use the Index Luke

Use The Index, Luke is a free guide to SQL performance for developers.

Unlike many other SQL performance tuning resources, Use The Index, Luke avoids unnecessary details about database internals but highlights the most important topic for fast SQL: proper indexing.

http://use-the-index-luke.com/

Clever Algorithms

The book "Clever Algorithms: Nature-Inspired Programming Recipes" by Jason Brownlee PhD describes 45 algorithms from the the field of Artificial Intelligence. All algorithm descriptions are complete and consistent to ensure that they are accessible, usable and understandable by a wide audience.

Get the book for free at it's official website: Clever Algorithms

Qt in Education Course Material

QT starting lectures are available for free from Nokia. You can download the lectures including speaker notes and exercises from here.

Stack Overflow ebooks

Stack Overflow ebooks contains books with the top topics on various questions in the Stack overflow site.