Integrated development environment (IDE)

      - Visual Studio Express Edition (.NET) : http://www.microsoft.com/express/download/

      - Eclipse : http://www.eclipse.org/downloads/

      - NetBean : http://www.netbeans.org/downloads/

      - Python : http://www.python.org/download/ 

Database

      - MySQL : http://dev.mysql.com/downloads

      - Postgresql : http://www.postgresql.org 

Toolkit / Engine / SDK

      - DirectX SDK : http://msdn.microsoft.com/en-us/directx/aa937788.aspx

      - OpenGL : http://www.opengl.org

      - 3D Engine : irrlicht.sourceforge.net

      - OpenCV : sourceforge.net/projects/opencvlibrary/