Online - Technical

O'Reilly Open Books

Common Lisp: A Gentle Introduction to Symbolic Computation

Creating Applications with Mozilla

Dive Into Python

Graphics Programming Black Book

Grokking the GIMP

GUI Development with Glade2

Handbook of Applied Cryptography

Linux Device Drivers 2nd Edition

Philip and Alex's Guide to Web Publishing

PostgreSQL: Introduction and Concepts

Practical PostgreSQL

Programming Linux Games

Ragget on HTML4 (Chapter 2)

Rainbow Books

Searching for Solutions in Games and Artificial Intelligence

Structure and Interpretation of Computer Programs

Thinking in Patterns with Java