How Come You're Reading My Blournal?

Something good has come from this holiday visit. Twice now, I've heard a person pick up a ringing cell phone and greet the other person with simply, "How come you're calling my cell phone?"

Not even a "Hello" or a "Hey (Tom, Jane, etc.), how come..."

Now, I don't own one of those infernal devices, but if I ever do, well, now I know how I'm going to answer it. I recommend you do the same. We could really start something awesome.