Programming

C/C++

• cplusplus.com
• Cprogramming.com - helpful forum
• Boost libraries
• wxWidgets - GUI library for C++ and Python

Java

• Java 6 Language Specification

Python

• python - official Python website
• LogiLab.org - useful tools related to Python

Android

• Android Developers - official Android website
• Hello, Android - Forum for the best Android development book. Ed Burnette, the author, is extremely helpful.

General

• Dr. Dobb's