General Resources

Textures

Texture Competition 0001 - Metal
Texture Competition 0002 - Camo
Texture Competition 0003 - Stone/Concrete
CG Textures

Code

GPL Code Repository
The Millionth Monkey Gets Its Typewriter - Movement Optimization

Sounds

Freesound contains high amount of samples even complete ones that are uploaded by users and licensed under "Creative Commons License", which in short - "If you use the files you need to attribute the creator of the file (i.e. say who made it)." Creative Commons License

Features

Compilation List of Features for Maps

Models

Model Base

FODB - Free Object Data Base