SharpDevelop is the open-source IDE for the .NET platform.
Supported Programming Languages:C#,VB.NET,Boo,IronPython,IronRuby,F#.
Windows Forms,WPF,Entity Framework
Refactoring and Parallel build support for multi-core machines
NuGet and T4 support
Multi-framework targetting (.NET 4.0, as well as 2.0, 3.0 and 3.5)
SharpDevelop Reports .NET open-source reporting solution
XML code completion