A couple of points:
1. The "universal" object you are trying to create is called a "singleton" (correct me if I'm wrong). Search PM or google for more information. Or look at singleton.
2. Although 'use'ing the modules specifically makes it easier for you and anyone else who looks at your code to see what's coming from where you might try to use one package to handle all these for you. Example:

package MyApp;
use Config;
use Login;
sub config {  return $config_object }
sub login { return $login_object }

## main script
use MyApp;
MyApp->config->do_something();
## or
my $config = MyApp->config();
$config->{do_something}
[download]

I hope this gives you an idea.

$will->code for @food or $$;