Thanks for the advice...
I was thinking that I may need to do something like invent a nightly "network-client upgrade" but I was hoping I could somehow make a back-up during the day while a given user is logged onto the network without them even knowing that it was hapening.
I'm going to keep looking, I'll let you know if I find anything. I would think that there would be something out there with all the "sniffers" and other hacker tools out there.