Some 20 years ago I was an a student at a university and a resident and network/server admin at one of the dorms. We had some people from a student organizatio

Some 20 years ago I was an a student at a university and a resident and network/server admin at one of the dorms. We had some people from a student organization which I will not name set up some servers with warez and other things in our network. This network was back then completely open to network and all students' machines had real, public, routable IP addresses and no firewall. We had to tolerate the people even though the rules stated running intensive services was not allowed and I would normally had a script that would automatically ban a user for doing something like that. I remember one day we (me and my roommate) decided to take a look at the server and we noticed it is some stock install of a Linux Mandrake which was known to be totally insecure. We decided to bet who is going to be faster to the server. Half an hour later we were both telnetted to the server and chatting using wall, of all possibilities. For those who don't remember, wall broadcasts messages to all terminals on the server. Couple minutes later the owner of the server burst into our room scared that some hackers just invaded his precious student service. You should see our faces.