Awesome Tool!
A must have for any .NET Developer!
Snippet Compiler has been out for over 9 months. Great for providing example code to another developers.
Very handy situations where you are quickly typing up a small amount of c# code and just want to do a quick compile to make sure it is syntactically correct.
Shown below is a look at its UI. You can use it to compile small snippets of console, winforms, and ASP.NET applications. Of course, it is not intended for full fledge application development - just code snippets.
It’s free and as light as notepad 
.
Download it here.
You unzip the file to the default directory it expects to create (“SnippetCompiler2DotNet2”).
Copy that dir to your “program files” dir. Run the exe.
You can create shortcuts for the app within the exe, in the tools
He has two versions of the tool. 2.0.8.3 for .NET 2.0 | 2.0.7.1 for .NET 1.1. So whether you're still in .NET 1.1 or a 2.0 developer you're covered.
Thanks to Jeff Key for provided such a stellar tool.