In the mid-30’s, a robot message carrier was introduced in London, England. It was called “The Notificator”.
The machine is installed in streets and other public places where individuals may leave messages for friends like informing them of their whereabouts or making or canceling of appointments.
In front of the machine, the user writes his message on a continuous strip of paper and drops a coin in the slot. The message then moves up behind the glass panel and remains in public view for two hours.
Today, there’s a web-based notificator. All you have to do is type in a twitter user’s username and click the Notificate button. You’ll be given a twitter search result on what the user’s been up to.