When enabled (see Configuration), many nifty features are available.
Custom capes, skins, and titles displayed on vanished users to those running Spoutcraft.

Custom permissions

In order to grant all these cool things, permission nodes are checked to define what a vanished player gets.
Below is the default, example spoutcraft.yml:
cloaks:
    moderator: http://s3.amazonaws.com/MinecraftCloaks/jeb_.png
    admin: http://s3.amazonaws.com/MinecraftCloaks/Notch.png
skins:
    moderator: http://s3.amazonaws.com/MinecraftSkins/jeb_.png
    admin: http://s3.amazonaws.com/MinecraftSkins/Notch.png
titles:
    vanished: '&&b%n%rVanished'
In this example, there is a cloak and skin "group" called "admin" and one called "moderator", and a title group of "vanished".
To give a user the admin cloak, grant them the permission node vanish.spout.cloak.admin
To give a user the moderator skin, grant them the permission node vanish.spout.skin.moderator
To give a user the vanished title, grant them the permission node vanish.spout.title.vanished

You can create whatever names you want for cloaks, skins and titles. These are just examples. 
Skins and cloaks

These values are URLs to images.The example above points to the official minecraft skin/cloak urls

Titles

Use && as the color code. So, &&b in the example above is setting everything light blue.
Use %n for the player's name.
Use %r for a linebreak