Script.NET

Script.NET or S# is a programming language that provides scripting functionality in Microsoft .NET applications. The syntax of Script.NET is similar to JavaScript. It is designed to be simple and efficient scripting language allowing to customize .NET applications. The language has a true runtime interpreter, and it is executed without generating additional in-memory assemblies. 
Script.NET is an open-source project.
External References.
ScriptDotNet.Homepage