Mine

#!/usr/bin/perl

use strict;

opendir DIR, "./" || die "can't opendir some_dir: $!";
foreach my $element ( readdir(*DIR) ) {
        if ( -d $element && $element ne '.' && $element ne ".." ) {
        print "$element \n";
                opendir SUBDIR , "$element" || die "Flaming death : $!\n";
                foreach my $file ( readdir(*SUBDIR) ) {
                        print "$file\n";
                        if ( -f $file && $file =~ /\.rar/ ) {
                                chdir (*SUBDIR) || die "Can't CHDIR to the subdir : $!\n";
                                system("unrar e \"$file\" ") or die "Can't unrar : $!\n";
                        }
                }
                close SUBDIR;
        }
}