With the Pronamic Domain Mapping plugin you can easily publish a page on the domain aliases or pointers of your hosting solution. This way you can easily publish landing pages on the extra domain names you own.
If you work with an WordPress Network and want to enable domain pages you have
to add the following line to your /wp-content/sunrise.php file.
$file = WP_CONTENT_DIR . '/plugins/pronamic-domain-mapping/sunrise.php';
if ( is_readable( $file ) ) {
include $file;
}