Dont know if this is well known IDE but just in case not:

#develop (short for SharpDevelop) is a free IDE for C#, VB.NET and Boo projects on Microsoft's .NET platform. It is open-source, and you can download both sourcecode and executables from this site. In addition, you can find the latest information and changes on #develop, as well as get in touch with the team in the forum.

http://www.icsharpcode.net/OpenSource/SD/


A8.3x Commercial, AcknexWrapper and VS 2010 Express
○pararealist now.