This forces my team to find creative ways to keep them working while also taking measures to isolate them as much as possible. I also use them to teach old exploits that have been patched in more recent versions, walking people through how it worked and why it existed.
I am interested in learning more about this. I know a fair bit about networks but exploit history and modern attack / defense strategies and server hardening are not my main specialty. Do you have any good links or resources that you can share?