I condensed golux's script by 4 lines. Hopefully, this might be a little bit easier to read.

#!/usr/bin/perl -l

use strict;
use warnings;
use CGI qw/:standard/;

my $index = 0;
if($index == 0) {
    my $cgi = new CGI;
    print $cgi->header(),
    $cgi->start_html(),
    $cgi->div({-id => 'pagewrap'}, "Hello"),
    $cgi->end_html();
}
[download]

Update: Condensed even more:

#!/usr/bin/perl -l

use strict;
use warnings;
use CGI qw/:standard/;

my $index = 0;
if($index == 0) {
  my $cgi = CGI->new;
  print header, start_html, div({-id=>'pagewrap'}, "Hello"), end_html;
}
[download]