January's MacWorld contained an item about turning off the guest access that is turned on by default in OS X so that the dropbox in the Public folders can be used. Included is a brief tutorial describing how to turn the Applescript into an Applescript Studio application. In the AS-Studio version your password appears as bullets, in the Applescript Version it appears as clear text. This should toggle guest access preferences if you've ever activated file sharing. You'll get an error if you haven't.