Bukkit

WorldEdit is an in-game map editor for both creative and survival

WorldGuard

The most used authentication plugin for Spigot and CraftBukkit!

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

The premier long-range map editing tool for Minecraft SMP.

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

Provides automated plots with protection (MultiWorld support)

LoginSecurity

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

a feature-rich world size limiting plugin, which can also generate or trim a world to your border

Lockette v1.4 - Simple chest and door lock, no databases!

Bssentials GroupManager

A simple plugin to protect villagers

High performance authorization plugin

CoreProtect

Grief Prevention

The banning plugin that does everything. Properly.

Stops people from breaking farmland

Lightweight Protection for Chests, Furnaces, Dispensers, and more

CombatLog aims to punish players who log out to escape combat.