There is a good article on refactoring on perl.com : A refactoring example

I learned A LOT about Perl by looking at my (and others!) old Perl code and going through the refactoring process - trying to improve what was already there, applying my new knowledge of Perl, and exploiting CPAN modules that I had become familiar with.

It's a good sign that you are critical of your own code and wonder if it's really the best that it can be. There are wayyy too many developers/admins/others that are content to write half-assed, barely functional scripts/programs/apps, stick them in production, and never look at them again.