Lex and Yacc (Bison) are tools that you can use to develop your own programming languages, scripting languages and interpreters:
These tools are included into Linux/Unix operating systems. They were developed by Stephen C. Johnson at AT&T.
This post is devoted to implementations of Lex and Yacc for .NET Framework and Java platform. Here is a list:
updated:2008-06-19:MinosseCC: a lexer/parser generator for C#