MobDisguise is a plugin allowing you to transform into any mob you want, with no client mods! Just simple type /md disguise pig, and boom, everybody now sees and thinks your a pig! Can't quite take out the enemy pvp team? Transform into chickens, and sneak behind enemy lines! It even includes an API for other plugins to hook into, and can change players into mobs too!
Official URL : http://dev.bukkit.org/server-mods/mobdisguise/
Servers using MobDisguiseServers: 0