Bukkit

The multiworld plugin made by ferrybig

Pre-generates chunks, quickly, efficiently, and safely

A Skyblock Plugin

PlotSquared

Creates cleanroom-style flat world generator with fully customizable layers. It can also be used to create empty space maps!

Nothing but void!

Creates Hunger Games styled arenas and gameplay

Provides automated plots with protection (MultiWorld support)

This plugin allow full control of normal world generator

CityWorld

A plugin for Bukkit based Minecraft server that adds a floating island dimension similar to the old skylands.

Exotic Garden

Its a plugin, but its mod-like: New mechanics, new worlds, custom bows and strucutres, faster game, survival reinvented.

Survive hordes of zombies as night stretches forever on

Floating island based world generation

for use with InfinitePlots and WorldGuard, creates regions automatically for new players

Add OP Items to your Game!

Giant Caves is a bukkit mod that creates giant underground caves in the world.

MagicLoot

IslandWorld - Survive on small isle