Instantaneous communication. From anywhere in the universe. And it really works. I watched an adorable Japanese cat jumping in and out of a box on YouTube, and I must be millions of light years away from Earth.
I'm not a particle physicist, so explaining Bell's Theorem is probably best left to the experts, but I'll give you a quick and dirty summation. Some of the core ideas require an accepting mind. However, as strange as these concepts are, Bell's Theorem has been verified in laboratories in our own lifetimes. This isn't theoretical stuff, it's very real.The gist: Once two particles are "entangled," they behave as a single particle in some ways. One of those is the inability to discern the position AND the velocity simultaneously (the famous Copenhagen...). So, if you measure one particle, it's entangled partner instantaneously limits what can be known about IT! I'm dead serious.
Here's what I can gather from the Bell Phones (my name... the coincidence with Bell Labs is just too much): Entangled particles are created and stored in flat discs the size of garbage-can lids. I have no idea what kind of magnets they're using to keep them in such a tight loop, but the particles spin around and around the outer edge of the disc, constantly passing through a read/write mechanism.Each phone is made up of three of these. One to transmit, one to receive, and one to keep time. The time, from what I understand, is very important. It assures simultaneity--without which, the following would be impossible.The phone on Earth is constantly trying to measure one feature (A) of its particles. If it can make all measurements successfully, nobody's transmitting. As soon as a measurement fails, it knows there's a caller, and here's why: the other side (wherever I am) is making measurements on its entangled pairs for (B). And both cannot be known at the same time. Any measurement made here limits the readings from Earth.From there, it's as simple as assigning 1's and 0's to feature (A) and (B). With that, you can transmit voice, data, even videos of cats jumping in and out of boxes. And... if you can read this... it really works!
(I've been informed of some syncronicity problems over the last week, which would explain any typos)