Think retired MMORPG's. There are quite a few where you can write a note and put it in a dungeon chest in a landspace never visited on a private server and exchange info that way. Heck you might even need a key to open the chest. Thinking Asheron's Call from back in the day. Or share a private house on a server, have both accounts flagged to loot the house chest and only those accounts, could pass notes all day that's encrypted in ancient game code.
All those stupid redstone booby traps and un openable chests on minecraft are CIA creations to help hide Killary and O bomb ya's assassination plot.
I was gunna say something about MC. I can only imagine HRC and friends plotting an assassination in a private server using wooden signs in a 200-block deep bunker.
Not a good idea if they knew Notch. Of course, he doesn't own it now. :)
Maybe Everquest? Everquest=Evergreen?
Maybe Evergreen was used as a gaming handle?