The Killer App for Google Glass
A politician such as Roosevelt meets lots of people over the course of his career. For each of them the meeting is an event to be remembered and retold. It is much less memorable to the politician, who cannot possibly remember the details of ten thousand meetings. He can, however, create the illusion of doing so by maintaining a card file with information on everyone he has ever met: The name of the man's wife, how many children he has, his dog, the joke he told, all the things the politician would have remembered if the meeting had been equally important to him. It is the job of one of the politician's assistants to make sure that, any time anyone comes to see him, he gets thirty seconds to look over the card.
My version will use more advanced technology, courtesy of Google glass or one of its future competitors. When I subvocalize the key word "Farley," the software identifies the person I am looking at, shows me his name (that alone would be worth the price) and, next to it, whatever facts about him I have in my personal database. A second trigger, if invoked, runs a quick search of the web for additional information.