No, but your approach sounds like a royal pain-in-the-ass, and has a few rough edges to it, like "She enters the person's current ip address". How does she know? Does she rely on them knowing? How do they know? What happens when they're coming in through a proxy server (e.g., AOL) that might change IP addresses between page fetches? Yuck, yuck, yuck.

I think you'd be better off setting up password protection for the directory. Augment it with some side bookkeeping so that you can expire users, or preallocate a number of users and hand them out on demand.

Or, if you don't want people to even know that there's a hidden page somewhere. provide a page with an unlabeled "password" box. Provide a one-time (or time-bound) password, and be "redirected" to dynamic content. Then, all your wife has to do is hand out passwords.