I know this one will mess with your minds. It's messing with mine, and I am the one who thought of it. Quantum computers are just around the corner--as are quantum cell phones. I'll spare you the complex physics involved, and just cut to the chase: Will quantum cell phones allow us to communicate with other quantum realities? The possibilities are endless. But one scenario could go like this: Tom (calling his home with his quantum cell phone): Hello, who is this? Grandma: This is your grandmother. Tom: But I thought you were d-d-d-dead! Grandma: I thought YOU were dead. Killed in that motorcycle accident, last year. I trust you can see what I am talking about. And if quantum cell phones (or even quantum computers, for that matter), don't let you communicate with other realities, why the heck not, then?
I don't believe you'll be able to talk to your dead Grandma. From my understanding, they'll still ultimately be filtered through binary hardware, it's just that the quibit processing will allow for things like much more complex passwords and extremely faster computers.
People tend to think quantum mechanics are all about how small something is, but they are metaphorical rather than metaphysical and the actual issue is how humble anything is relative to the observer and the context. Primitive tribes knew this before the invention of agriculture and, to this very day, talk to people in alternate universes without requiring fancy technology. Combining technology and ancient wisdom means the future will be more like Star Wars than Star Trek and you'll be able to call Dorthy in the land of Oz if you want, that is, assuming she hasn't gotten an unlisted number and your karma is compatible. The nonlinear temporal dynamics are what everyone notices first because nobody can mess with your own head like your future self.
my dreams allow me to do so now. or some of them do. i think cell phones are rediculous with thouse tiny little screens and tiny little keyboards. they were obviously designed for tiny little elves in other universes. but a multiversal internet might be fun, if we could keep local media from blocking access to worlds where people don't hate logic and have cultural perspectives unfamiliar to the parts of our earth fortunate to have access.