Version: v1.5.3(release) [1.7.9-R.2]
This plugin adds locked doors to your server that can be unlocked by obtaining their matching colored key ("key" meaning a chat message explaining you have a key, until Spout allows custom items :p). You can either obtain a key through a player with the appropriate permission, or an NPC with permissions enabled (when questing). This will soon add a certain, special layer of classic role-playing and questing that has yet to be seen in a Bukkit plugin.
Note: The YouTube video has been removed due to out-of-date methods (changed with version 1.3.0). A new video will be released shortly.