
While they have a community GM Holocron, I've decided to do my own instead. I am having issues creating stuff on theirs. If one day I gain the right permissions to add pages, I'll contribute a lot of content.
Basically, a GM Holocron is a stockpile of resources designed to make the arduous task of planning and setup of a session easier. The GM Holocron is a document/folder/ file system that will contain lists of NPC's, equipment, adventures, images, ships, and encounters (called set pieces). I would normally have just used InDesign or Publisher, but I have recently found Evernote which is perfect for what I want to do.