My institution is interested in providing in-house-only access to digital materials we can't simply put online -- copyrighted material, restricted materials, etc.
We currently embed digital materials directly into finding aids, and want to avoid a system that would involve implementing a separate access solution (and we know our patrons aren't interested in setting up accounts/logins, either). We are currently exploring the use of IP addresses to restrict access to the digital content to computers physically located inside our library reading room. Ideally, anybody would be able to look at the finding aid, but only IP addressess in the permitted range would be able to click through to view/download the actual digital content.
Does your institution or any other institution that you know of do something similar? Have you explored IP address restrictions for your institution? What advantages and disadvantages did you find? We're hoping to avoid re-inventing the wheel if we can.