SICP

+------+
|      | You have been visited by the SICP OF SATORI!
| SICP | Programming skill and enlightenment will come
|      | to you, but only if you post a metacircular
|      | evaluator in this thread.
+------+

>>4
is that common-lisp?
tried it in racket and got

interaction-environment: undefined;
 cannot reference undefined identifier