Tools

BuGLe
A tool for debugging applications that use OpenGL.
http://bugle.sourceforge.net/

FRAPS
FPS (Frames Per Second), video capture, and screen capture for DirectX and OpenGL applications.
http://www.fraps.com/

gDEBugger - OpenGL debugger
Commercial OpenGL debugger
http://www.gremedy.com

glsldevil - OpenGL GLSL Debugger
A tool for debugging the OpenGL shader pipeline, supporting GLSL vertex, fragment, and geometry shaders. Includes screenshots, documentation and downloads.
http://www.vis.uni-stuttgart.de/glsldevil/

The SphereXP
3D desktop replacement for Microsoft Windows XP
http://www.hamar.sk/sphere/