Bukkit

Vault is a Economy/Permission plugin for hooking into the various Economy and Permission plugins.

WorldGuard

A collection of useful commands and features for server admins and players.

EssentialsX

Plugin Manager For Bukkit

Allows server admins to easily modify how Minecraft works without programming anything

Tablist

A plugin which teleports you to your set home.

An mcMMO themed plugin for horse role-playing.

Change your ingame skin

SetSpawn

Fully customize any mobs (and create custom mobs) with a powerful scripting skill system, attributes, equipment, special AI, and much more, along with custom spawners and spawning rules. The ultimate plugin for making RPG servers and minigames.

Light weight and easy to use!

mcMMO

Mobs will be teleported up until they are no longer suffocating

A plugin to warn your players when your server will restart!

BukkitGUI - the most downloaded GUI for bukkit and any other server

Gives the ability to cut down trees at once. Just like Timber mod.

Change the colour of the server chat!

An addon to the popular addon Skript that exposes the Bukkit API to general server owners