cfg_map

cfg_map adds a page to the core Nagios GUI that maps out your objects in your .cfg files.

You get a quick hierarchical map of object relationships:
use hostgroups servicegroups contacts
plugins commands timeperiods files

Great for bringing a new developer on board, or for finding your way around a large set of objects.

For example, an object with "use XYZ" in it, will be a child of "XYZ" in the Use hierarchy map. (See image)

Similarly, any object with a "hostgroup XYZ" will be a child of "XYZ" in the the Hostgroups hierarchy map.

If an object is encountered that has no place in the hierarchy, it will be listed in "no_hostgroup" for example.

Great for finding uncategorized hosts and thinking about where they should better fit into your config.

This is a simple PHP page, with trivial install/uninstall, so don't be afraid to download and try it out.