Non-Gamer's Guide to This Post
When a player needs to step away from the computer, or go away-from-keyboard, they type /afk and their character is marked as AFK: Away From Keyboard.
Likewise, when a player is on but doesn't wish to be disturbed, he or she can type /dnd which marks them as DND: Do Not Disturb. This is for players who are active on their characters but don't wish to interact with others.
When someone tries to contact one of these characters, an automatic message will be returned giving their status. Likewise, the AFK or DND shows in the open friends panel.
Apparently, this neat trick has been around forever, but I just found it, like a goldmine of love.
When you type /afk or /dnd, you can put a note with it.
/afk Updating blog.
This player is AFK: Updating blog.
I'll add some example pictures later.