Bukkit

Entities drop their Name Tags upon death

Controls player, block, and mob item drops.

BlueStorm

Very interesting and unusual plugin that adds a crafting cheap acualung gear.

Offline-Auth plugin with MongoDB support

Infinite dungeon crawl generator

Disables the natural despawning of items.

Become a Time Lord and regenerate!

Bye Bye Nether Portals

SMP Extender

Bukkit / Spigot Plugin

Lets your players report each other

Elytra Landing is a minigame where you have to land on platforms using elytra

With this plugin you can change the items of fishing and bring your server to a whole new level.

Upgrade your sword!

a fully customizable complex rpg plugin

Realistic chat system to replace vanilla chat.

Opinion (Votes System)

RedstoneMobSpawner allows controlling mobspawners via redstone

it is a anticrash plugin for your server