<i>No one really comments like that , its unnecessary and if it causes problems then a simpler form should be used.</i><p>I comment like this.  It's also not hard to do.  You type something like:<p><pre><code>  some line of code ; here is my comment, blah blah blah, very long, blah blah blah
</code></pre>
Then press M-q ("fill-paragraph"), and Emacs turns it into:<p><pre><code>  some line of code  ; here is my comment, blah blah
                     ; blah, very long, blah blah blah
</code></pre>
Sometimes this looks nicer than:<p><pre><code>  ;; here is my comment, blah blah blah, very long,
  ;; blah blah blah
  some line of code
</code></pre>
Anyway, both styles are quite common.<p><i>"Or consider someone who is on an 80x25 terminal"... ok now where are just getting silly.</i><p>I always consider people on 80 column terminals, because although I have a huge monitor, I would like to display more than one file at a time.  Aiming for 80 columns means that you appeal to the "lowest common denominator" and it means that you can have lots of files within easy visual reach.  (I actually end up near 90 at home and 85 at work... but I try not to exceed 78 too often.)