Hmm...well, you can request a remote file in various ways (in which case it could be local or remote). Here's a page that describes this:
http://www.php-mysql-tutorial.com/wi...using-php.aspx , but I'm guessing that's not what you want since you'd want the external script to execute like it was called by the user that requested *your* page.
You can include a file but it will be executed and will send out an entire HTML page as a result, and that's probably not what you want. [S]And you can't put "?do=something" on it.[/S] (ETA: I was wrong - see later comment)
You could probably adjust the global variables then include a script and capture the output like this:
Code:
$_REQUEST['do'] = 'something'
ob_start();
include('index.php');
$includedphp = ob_get_contents();
ob_end_clean();
but then you'd probably have to do some processing of the resulting string to get what you want.