(Lt) Commander Data: Star Trek: The Next Generation (ST: TNG) premiered their Pinocchio of the 24th Century in 1987. Data is remarkable for many reasons but the most curious is that he is not only anatomically correct but also fully functional. Why is this important? Well, I suppose it was just in case someone literally needed a "Love Machine" such as the case of a horny Tasha Yar. On the other hand, maybe it was to help Data in those awkward instances when he was stripping down in the locker-room with Picard and Ryker after a rousing game of 3-dimensional chess.
(Image courtesy of Wikipedia)