Hey, just an idea or maybe someone has made a plugin for this? Basically theres a open kit pvp area with people fighting and people who get a set amount of kills or killstreak get a title above their head (tagapi it or something). So players know who is like bossing in pvp so they can either avoid them or take them down. Also maybe players get rewarded for having this rank of which will be removed when they log out. Also maybe when on a killstreak you get a buff too. Please let me know if there is already a plugin out there like this or you may consider making it! Thanks -Mineshaft
http://dev.bukkit.org/bukkit-plugins/killtitle/ Wait for it to be approved and you'll be right along!
Source? I might want to change or add some things to this once its's out. (Yes, credit will still be given)