On second thoughts, best not bother. You're not going to beat the Janken robot. It's impossible.
The creation of Tokyo's Ishikawa Watanabe Laboratory (they do some very clever stuff with computers and sensors), the third iteration of their Janken robot has a 100 per cent win record in the timeless game of Rock-Paper-Scissors.
It's not cheating - it's just using a high speed camera to read a human's hand movements, calculating their opponent's choice and producing the winning option in around one millisecond.
The camera images your hand as a silhouette, reading the fine adjustment between finger movements (flat for paper, curled for rock, pointed for scissors) to predict the eventual shape of the hand.
Real life applications? Well, other than humiliating every child in the playground, this sort of fast-reaction-response scenario could find use in robots that interact with humans. Which is sort of terrifying.
Best out of five? How about an arm wrestle instead...