Now i entered again to MC forums, I have a great great new!! I don´t know if mojang read this, but magicly, a new block is going to be added to the next upádte: Hopper; items dropped on it, can be stored in chests and at in-hover inventory.
Well, my idea was to drop a book and quil (with a message written on it) on this "block". Because it is not going to disappear 5 miuntes after (like al items), another player will be able to collect it when he connects. He will be able to read my message.
Someone said that it can be possible with chests.. but in my server there is not police.. People would steal another people messages, it would be a mess!.
Fortunately, mojang created Hopper block... mailing, automatic farms, etc
Since he just said the hopper is added and this idea is practically obselete, why do we even need this anymore? Not trying to backseat moderate (though unfortunately I am) I think this thread can be locked.