I am sure that something like this exists, but I cannot let my life remember what it is called.
I am looking for an application in which I can simply execute an arbitrary block of C # code and see any console output.
http://www.sliver.com/dotnet/SnippetCompiler/
Fragment Compiler
snippet, :
, , Console.WriteLine(...).
, .
LINQ Pad. snippet linq sql.
GSharp, .
http://tirania.org/blog/archive/2008/Nov-02.html
TestDriven.Net, Visual Studio ,
, , .
, :
LINQPad is my favorite :)