One time I was working with a coworker on a UUV on the manufacturing floor. I paused to look something up on my Android and I told him "I love this -- it's like a secondary brain in my pocket."
Guy from manufacturing happens along. "I've got a secondary brain in my pocket too. It gets me in trouble most of the time."
He's got it backwards. The world isn't the exobrain for humans, humans are the exobrains for the world.