Credits to ecube (ClassyRain) for coding, Zeroknight for idea, Gingerbear for another idea, and Rage for help with testing.
Special thanks to quin and graphitemaster for help

The info is shown at the top (IP, CN, name).
Put the server.cpp in the src/game directory, and compile it if you wish to use it.
Current functions:
/getip CN (only works for master and above, make sure you set sv_serveropen to 3)
Shows the IP and CN of incoming players to master and above.
Claiming admin or master on a server (if you're not authed) gives an extended message.
The diff: (all those "muted" things were fails, I'll work on those later, but for now, they're commented out)
The #getip thing was also a fail, and was commented out, please ignore that. Use /getip instead.
Diff:
http://pastebin.com/2n3udiEL