The interpreter has thirteen built-in functions: car, cdr, cons, eq, atom, set, eval, error, quote, cond, and, or, list. These include the five elementary functions on s-expressions defined by McCarthy; some conditional expression operators; an assignment operator, and some functions to control the evaluation process.
Homepage: AWK Lisp: Lisp implemented in AWK
References: Common Lisp Implementations - The ALU Website