use Date::Calc qw(Today_and_Now);
  my ($year,$month,$day, $hour,$min,$sec) = Today_and_Now();
  my $dir="$day-$month-$year";
  mkdir($dir);
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I think this is cleaner and more readable then other proposed solutions. ( Date::Calc is a big module though ).

Now, I would recommend rethinking your 'day-month-year' style, with 'year-month-day' you get more logical view (it sorts nicer)

And another thing - with daily backups very soon you'll find out that what you got is linear list of all those backups... 300, 600, 1000 entries... not a nice thing to look at, not that easy to find what you need etc, try hierarchical structure: "$year/$month/$day/BACKUP", all you need is mkpath:

        eval { mkpath($dir) };
        if ($@) {
                print "Couldn't create $dir: $@";
        }
        chdir($dir)||die;
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