Reflector is a class browser, analyzer and documentation viewer for .NET. Reflector allows to easily view, navigate, search, decompile and analyze .NET assemblies in C#, Visual Basic and IL.

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Resourcer is an editor for .resources and .resx file formats used with the .NET platform. Resourcer allows editing of strings, import of bitmaps and merging of resources from different sources.

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Writer is a simple editor for HTML files. Writer supports text layout and formatting, hyperlink editing and insertion of dates and pictures.

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Mapack is a C# class library for basic linear algebra. It computes Norm, Determinant, Cholesky, LU, QR, SVD, least squares and eigenproblems.

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The CommandBar class library extends Windows Forms with classes for handling command bars and bitmaped menus.

Source here.