I'm pretty sold on the OO approach, but there are a few additional wrinkles I neglected to mention. I agree that having a perl-based config file is very handy and easy to use. When we do so, we typically want to use info from the machine config inside the app-specific config file. So...

# In my cgi script...
use My::Config;
my $config = My::Config->new(project => 'GuestBook');

require $config->get('config_path') . "app_config.pl";

# Now, inside app_config.pl, what's the best way to get at the config
# object if I want to use some of the methods?
# Just create another new object? It seems wrong to do it again,
# but I suppose the overhead
# is probably trivial.

# Inside app_config.pl

package My::App;

use My::Config;
our $config = My::Config->new(project => 'GuestBook');

if ( $config->get('env_dev') ){
  # We're in dev, so set the dev passwords.
}

# etc.
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Now, how do you feel about then using the $config object as a package variable to access it in other code that is part of the framework but outside the scope of the original script? Using the code above, I could then do this, right?

package My::App::Page;

my $db_password = $My::App::config->get('db_password');
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