Bukkit

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

SetSpawn

Slimefun

Change your ingame skin

A plugin which teleports you to your set home.

Portals module for Multiverse-Core

The multiworld plugin made by ferrybig

Library for intercepting sent and receieved Minecraft packets.

Tablist

Guilds, war, land claiming, and user-controlled antigrief

Dynamic web-based maps of your Bukkit/Spigot server

Open anyone's inventory as a chest in real time!

Provides essential server managment tools: World autosave, Backups, Auto restart, Plugin data purging, Plugin management and more.

A simple and powerful backpack plugin with SQLite and MySQL storage.

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.

Marriage Master

show the kills an death with the Scoreboard

A Skyblock Plugin

Detect and fight the exploitation of various flaws/bugs in Minecraft!

Chat management plugin for nearly every permissions plugin.