RenderMonkey Toolsuite
RenderMonkey contains a full featured shader editor, allowing for rapid prototyping of shaders. The integrated shader compiler and preview window provide immediate visual feedback for the effect under development — ensuring that errors in programming are identified early in the development process.
Shader Tech
A Web sites focused on modern GPU programming. Includes news, forums, tool, tutorials, and articles.
ShaderWorks
ShaderWorks is a new breed of hardware HLSL shader development tools for DirectX 9.0 which is comparable to ATI's RenderMonkey, but with a Visual C++ 7.0 style visual (graph-based) interface for loading and linking re-usable HLSL shader blocks (inputs, outputs, textures, functions and constants).
Sharky Extreme
Reporting on the latest hardware and software technology for the PC enthusiast.