Bukkit

Logs all messages, and when Chester is mentioned, he replies with a logged message.

Foobar

you can have multi-inventories and easily switch them.

Automatically applies an invisibility effect to players on login. Useful for BungeeCord hub servers.

Adds a command to allow a player or the console to list all objectives on the main scoreboard.

Adds a 'shadow-ban' function: Hides specified player chat from everyone but themselves

Plays a 'ding' sound when your username (or shortened nickname) are mentioned in chat

When bonemeal is used on cobblestone, turns it into moss stone.

Gives the specified player every gosh-darn achievement in the game

Adds the vanilla command /effect to Bukkit

Adds a label in chat messages showing the closest Essentials warp to a player

The complete Fireworks plugin!

Allows players to create a block at their location, even if they're flying

Allows you to set Name of item, Description of item, and add a from/to tag for gifting.

When a block is broken, it adds a line to the lore saying who broke it

Retrieves 'Now Playing' information for a user from last.fm

Note-taking plugin for moderators/administrators that uses MySQL

Allows server owners to restrict block interaction in The End, and logs when a player kills the Ender Dragon

The player that kills the Ender Dragon receives a dragon egg in their inventory. Made by request.

A plugin that shows a player's in-game coordinates on command.