Engineers at the Ishikawa Oku Laboratory at the University of Tokyo have developed at Janken (rock, paper, scissors) robot that cannot be beat.
Here’s a summary of the research from the Ishikawa Oku Laboratory website:
In this research we develop a janken (rock-paper-scissors) robot with 100% winning rate as one example of human-machine cooperation systems. Human being plays one of rock, paper and scissors at the timing of one, two, three. According to the timing, the robot hand plays one of three kinds so as to beat the human being.
Some of the commenters on YouTube feel as though this robot may also be good for some other personal activities, but I choose to keep my mind out of the gutter.