Some cli applications and an application to make running them simpler. If you put jshell in your environment they are that much easier since you won't need to remember the path.
This started with a challenge from Brian S. at the Joomla Day NYC 2012, and I've been adding various other ones since then.
The files are expected to be located in a folder at the same level as your libraries folder. In CMS terms that means in a folder off of the Joomla root.