PLiX (Programming Language in XML) is an XML-based code-generation framework. Generators produce XML matching the PLiX.xsd schema, which can be formatted into multiple languages. Extensible formatters support C# and VB.NET in Visual Studio 2005 and 2008
A multi-language IDE written entirely with C#.NET. My goals include giving developers a framework that will allow them to add new languages, provide diagramming services to support language modeling and visualization (eg UML Class Diagrams, etc).