A Galton board has a hexagonal array of pegs on a tilted board with slots at the bottom. A ball rolls down the board, bouncing on the pegs until it falls into a slot. The outcome of each contact between the ball and pegs is random; thus, the probability that it will end in a particular slot is modeled by a binomial distribution. As the ball falls, the distribution of the ball's final slot is updated in real time, decaying to a point mass as the ball's final position becomes definite. You can change the speed; the maximum speed makes the ball jump instantly from one row of pegs to the next.