Downloading P#

P# is a Prolog implementation which translates Prolog to C# source code. This allows interoperation between Prolog and C#, and in particular allows you to combine Prolog back-ends with C# front-ends. P# is based on Prolog Cafe, a tool which translates Prolog to Java.

Ximian C# compiler

The Mono Project is an open development initiative sponsored by Ximian that is working to develop an open source, Unix version of the Microsoft .NET development platform. The Mono C# compiler is considered feature complete at this point and relatively mature.

devAdvantage : C# Source Code Analyzer for Visual Studio.NET

A 3rd party Microsoft Visual Studio.NET Add-in that provides C# static source code analysis to automate code reviews and detects errors, bugs and issues. The Community Edition is a free, fully featured, unlimited use version of devAdvantage that does not contain the threading knowledge pack.

csUnit

Inspired by JUnit, csUnit brings the power of unit testing to the .NET framework. csUnit is your key to test-driven development using .NET languages such as C#, Visual Basic .NET, Visual J#, or Managed C++.

#develop

#develop (short for SharpDevelop) is a free IDE for C# and VB.NET projects on Microsoft's .NET platform. It is open-source (GPL), 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.

DotGNU Project

The DotGNU project aims to be for webservices and for C# programs what GNU/Linux is rapidly becoming for desktop and server applications. DotGNU Portable.NET, an implementation of the Common Language Infrastructure (CLI), more commonly known as ".NET", includes everything that you need to compile and run C# and C applications that use the base class libraries, XML, and Systems.Windows.Forms. Currently supported CPUs: x86, ppc, arm, parisc, s390, ia64, alpha, mips, sparc. Supported operating systems: GNU/Linux (on PCs, Sparc, iPAQ, Sharp Zaurus, PlayStation 2, Xbox,...), *BSD, Cygwin/Mingw32, Mac OS X, Solaris, AIX

Visual C# 2005 Express Edition

Visual C# 2005 Express Edition is a simple, lightweight, integrated development environment designed for beginning programmers and non-professional developers interested in building Windows Forms, class libraries, and console-based applications. Visual C# 2005 Express Edition includes many of the same productivity features found in Visual Studio, all streamlined to fit the needs of the non-professional Windows developer.

Turbo C#

This is part of new line from Borland for students, hobbyists and non-professionals interested in NET and Windows programming. The free explorer version comes with a comiler, IDE and built in components but is not extensible. There is also a professional version, which is not free but is extensible. Free registration is required.

C# Builder Personal Edition

For non-commercial Windows development only. I'm pretty sure you need to register for free and give them a valid email before you can download.