Algorithms

Sorting Algorithms
Visual Sorting

Abrash

Graphics Programming Blackbook The Zen Master of Graphics Programming
Graphics Programming Blackbook in Markdown

Knuth

The Art of Computer Programming

General

Up and Down the Ladder of Abstraction
An Extensive Examination of Data Structures Using C# Not being maintained, so sad.
The NATURE of Code Vectors, particles, physics, fractals and more
Khan Academy
Googles Search Algorithms, Explained Here's the Cheatsheet