- L4 is a Forth interpreter written in Common Lisp.
- Warren Wilkinson shows how to build a Forth interpreter on the Formlis blog: http://formlis.wordpress.com/2010/06/30/forth-in-lisp/
- Doug Hoyte's Let Over Lambda has a chapter on building a Forth compiler.
Forth is a structured, imperative, reflective, stack-based programming language. There are several implementations available for Common Lisp: