FightClub is a Minecraft Bukkit plugin meant for creating arenas in which users can fist fight.
All you have to do to install FightClub is drag and drop the jar into your plugins/ folder on your server.
fightclub.fight - Gives access to all user-targeted commands. /fight, /fightaccept, /listarenas
fightclub.admin - Gives access to all arena creation commands. /createarena, /setarenaspawn
/fight <player name> <arena> - Challenges another user to a fight in the specified arena
/fightaccept - Accepts a challenge sent by another player
/listarenas - Lists available arenas.
/createarena <name> - Creates an arena with the specified name.
/setarenaspawn - Sets an arena spawn. Only works after /createarena has been used.