[support] Automatic update.php

Hi every one, I'm going to be maintaining a bunch of drupal sites. I'm trying to automate as much of maintenance as possible and one of the things I would like to do is update the database via a script, basically run update.php with the latest upgrades selected. The problem is that I can't just wget update.php and I didn't see any thing helpful in the scripts directory. Even worse is that google came up with Nil. Any one have any ideas on how I could do that? Thanks.