i don't know. Taking a clojure example :<p><pre><code>    (defn say [word]
      (println "You said"
               word))
</code></pre>
This wouldn't be possible without fixed width. Now a lot of languages don't use that kind of indenting a lot, but in lisps it's mandatory.<p>Also fixed width ensures that you can write code and it will lay in the same way on other computers, regardless of what other fixed width font they're using. That's a big big point i think, since code is most of the time a collaborative effort