Slimefun is a plugin which aims to basically turn your Bukkit Server into a modpack like FTB without installing a single mod. It offers everything you could possibly imagine. From Backpacks to Jetpacks to Andriod Automation… It also adds an API allowing you guys to easily install or code Addons for this. If you own a server where your players are getting bored of simple vanilla survival then you will absolutely love this Plugin! It adds a whole new Layer of Survival to your Server by adding more than 400+ new Items and hours more of progression!

Full Wiki can be found here