my @files = qw(here there anywhere);
foreach my $f (@files) {
    use $f;
}

##</code><code>##

use vars qw($big_directory $lil_directory);  # not 'my'
do 'config_stuff.pl'
    or warn("Problem with config_stuff.pl");
Then, in <code>config_stuff.pl

##</code><code>##

$big_directory = '/some/where';
$lil_directory = '/some/place/else';