A "walk" on the digits of a number can be used to evaluate the normality of a transcendental number in base 2 [1].

In this Demonstration a two-dimensional walk with unit steps is created by blocking the binary digits into pairs and assigning each of the four possible pairs to one of the four directions: northeast, southeast, southwest, and northwest. The walk of a base-2 normal number is expected to resemble a random walk and should not wander increasingly far from the origin.