This DevBukkit page is being updated again with current releases and links to the maintained uSkyBlock project.
Pre-generates chunks, quickly, efficiently, and safely
MagicLoot adds a whole new RPG Experience to your Server!
This is a basic world generator that creates empty worlds. It's lightweight, easy to use, and very basic.
Floating island based world generation
IslandCraft changes the biome distribution of the world to create an endless ocean filled with randomly generated islands.
SkyBukkit seamlessly brings SkyBlock to Bukkit servers.
A hunger games server mod designed for use with the Hunger Games Map Generator.
PlotMe manages multiple plot worlds with individual configurations, enabling owner-only building and road protection against griefing.
iclaims.plot.admin.remove - Allows you to remove other players plots, removing anything they built and their build rights on that plot.
Giant Caves is a bukkit mod that creates giant underground caves in the world.
Source on GitHub | Changelog | TerrainControl forums
The great outdoors is all good and fine but sometimes you just want to go to town.
This plugin provides a simple generator for server admins to use to create an infinite world of building plots (of a configurable size), the idea is for it to be used to create a world to be used for building competitions.
This plugin can be used by world managers such as MultiVerse (version 2.0+) as a Custom Chunk Generator to create customisable flat clean room style worlds.
This plugin will add a replacement for the default skylands world generator, the one in the game was never finished.