futuristic return address labels

And I also wonder about the futuristic possibilities of simple return address labels. How will they change? Well, even simple ones pasted on a paper envelope in the future can contain computer chips or RFID tags. They will track where the letter is the mail and whether the receiver has gotten it and opened it. If someone sends you a bill you don't want to pay, you won't be able to claim you didn't get it. Same with various legal notices. Maybe even with personal letters, though who writes those anymore? It'll also make it hard to tell creditors "the check is in the mail," because then they'll want the tracking ID so they can verify that, and of course you won't have it. But it will make delivery of mail a lot more accurate. No more letters taken home by mail carriers (some carriers have been found to have stolen/dumped tons of mail in their careers.)