SharpDevelop

SharpDevelop screenshots

It is an IDE for C#, VB.NET and Boo projects on Microsoft's .NET platform
Main window
SharpDevelop 4.2 beta : Main window

Alternative downloads

NetBeans IDE
Helps you to develop Java desktop, mobile, and web applications.
8.2
FREE
Infragistics Xamarin.Forms
Global Sales Dashboard API for Visual Studio for smartphone app development.
15.1.102
Sharp Snippet Compiler
The program is a tiny C# IDE with all the necessary basic tools.
1.1
FREE