There's a variable called safe_mode - at the moment, when turned on, only superusers are allowed into the site; everybody else gets an HTTP 502 error code. You can have apache generate a custom error page and put the login form on that; once the user is logged in and has a cookie, they'll see the site normally. There's only the login process that they'd usually have with Scoop, not the typical HTTP auth process where if they close the browser they're "logged out" again.

The bit that MH did but hasn't yet submitted makes safe_mode access based on a permission. So you could create your users and put them in a group with permission to access the site in safe mode...

I'll harass MH to submit it :-)

--
Discuss the art and craft of writing

It seems to me like this could be done through a combination of themes and permissions. Granted, it's not a simple setting, but I think it'll be less involved than hacking the code. I also don't have time to figure this out entirely right now, so I'll just outline what I'm thinking about and let someone else tear holes in it.

First, you'll want to take away all of the Anonymous group's permissions, including setting all of the the section perms for them to Hide or Deny. That way they won't be able to view anything, which I suppose accomplishes most of what you want.

Then, to make it easier to use, you could use themes to show Anonymous users a different main page than regular users. You could make index_template be just a login box for anonymous users, and make all the other _templates blank so that any other page a user hits has nothing. Then they would have to login to see any part of the site.