Question : Can I make Sharepoint sites or folders invisible to users without rights?

We're running Sharepoint Services 3.0 and have several sites (tabs) set up by department and function.  We'd like to set up a site that is only visible to selected users, e.g. executives.

I know how to restrict access to a site, which generates an 'Access Denied' error when an unauthorized user tries to browse to it, but I'm wondering if there's a way to make it invisible unless they have rights to it.  Also, is it possible to do this with shared folders?

Answer : Can I make Sharepoint sites or folders invisible to users without rights?

SharePoint Services only has the 3 options you have mention MOSS has the others..

Folders should not appear to users that do not have the rights to see them.  Tabs on the top also will not appear if you had SharePoint create the tab when you created the subsite.  If you added the tab manually, by default it will appear to all users, but they will get access denied when the click on it.  Why it is different one way vs the other?  I have no idea

Same thing seems to apply for the quick launch bar.  If it creates the entry, users cannot see it if they do not have access, if you create it they can and get access denied