Bukkit

With this API you can create Guis in 45 seconds

A good anticheat and i hope it will be a great on

RE: Core for bukkit is a dev tools and a admin tools

NameplateAPI

GUI for basic player/admin server controls!

Force Clients to use a certain texture pack.

This allows deveopers of multiple plugins to use the same scoreboard.

Build a Factions plugin for every version of Factions and not have to worry about version upgrades and changes.

Simple library for timer countdowns

Exports a digestible public JSON of SignShops available on the server

a powerful performance optimization plugin designed to manage and reduce your Minecraft server's RAM

API connection for cuboid plugins

MazeMania is a mix of arena, added a bit of mobarena and spiced with some sweet thinking of the PlugMania devs.

Automatically translates game chat between languages for free.

Allows you to add custom commands on your server.

ClearChat - Updated to new syntax!

SignThatBlock

Warp

A whitelist management plugin.

ItemLib makes it easy for developers to modify item attributes.