How would I code that?
Basically.. I have this, a working multikey login code.
mob/characters/Login()
if(src.currentipaddress)
for(var/mob/characters/X in world)
if(X.key!=src.key)
if(X.client && src.client)
if(X.currentipaddress==src.currentipaddress)
world<<"<b>Multikey Info: [X]([X.key]) and [src]([src.key]) share the same IP address.</b>"