ParallalCsharp, WolframOnSearch, PostSharp, …etc

Parallel C# is a new parallel programming language, a “smooth” extension of C# language.
We acknowledge the influence of several languages, such as T++, Polyphonic C#, ML and others.
http://www.parallelcsharp.com/

A Library of Software written in C# with full source code.
http://cplus.about.com/od/codelibraryfo2/A_Library_of_Software_written_in_C_with_full_source_code.htm

Wolfram gets on the Search Stage
http://www.wolframalpha.com/

PostSharp is a tool that can reduce the number of lines of code and improve its logical decoupling. Therefore its helps you delivering higher stability, cleaner design, and cheaper source code maintenance.
http://www.postsharp.org/