Microsoft’s Brad Abrams and Somasegar both posted about a set of standard Microsoft icons that ship with Visual Studio 2005. They can be found in a zip file in the Visual Studio 2005 installation directory (usually C:\Program Files\Microsoft Visual Studio 8\Common7\VS2005ImageLibrary\VS2005ImageLibrary.zip). There are over 600 icons in total with a mixture of Windows, Office and Visual Studio icons, and are licenced for reuse in your own applications.
I can't remember where I read it...
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