[chicago-lisp] Aha! moments in LISP (what are yours?)

[David Douthitt]

David Douthitt wrote:
> A Smalltalker (another *great* language) who enjoys LISP almost as much 
> took note of a thread about Aha! moments in LISP.

So what were *your* Aha! moments?  To me - to date - these were some
of mine:

* Realizing that text formatting had *nothing* to do with printf()
formatting.

* Building an application - like layers on an onion (or better yet, a
baseball): start with a core, wrap it, wrap that with another
function, wrap that....

* Understanding how macros really worked (from "On Lisp")

What are yours?