I don't have to remember to put 1; at the end of every new module I write, as my editor is configured to do it for me:

(defun perl-boilerplate () "Basic perl template." (interactive)
  (if (or (not (file-exists-p (buffer-file-name (current-buffer))))
          (= 0 (buffer-size)))
      (let ((strictures "use warnings;\nuse strict;\n\n#use Data::Dump
+er;\n\n"))
          (cond 
           ((string-match "\\([^/]*\\)\.pm$" buffer-file-name)
            (let* ((case-fold-search nil)
                   (package-name
                    (replace-regexp-in-string "/" "::"
                      (replace-regexp-in-string
                       "^.*/[^[:upper:]][^/]*/\\|\\.pm$" "" 
                       buffer-file-name))))
              (insert
               (concat "package " package-name ";\n"
                       "\n=head1 " package-name
                       "\n\n=cut\n\n"
                       strictures
                       "\n__PACKAGE__\n"))
              (backward-char 14)))
           ((string-match "\\(?:\.\\(?:p\\(?:er\\)?l\\|t\\)$\\)\\|^[^.
+]+$" buffer-file-name)
            (insert
             (concat "#!/usr/bin/perl\n" strictures)))))))
(add-hook 'cperl-mode-hook 'perl-boilerplate)
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Opening a new .pm file creates this:

package My;

=head1 My

=cut

use warnings;
use strict;

#use Data::Dumper;


__PACKAGE__
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while opening a new .pl script creates this:

#!/usr/bin/perl
use warnings;
use strict;

#use Data::Dumper;
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YMMV.