Easy Brush Variation is a plugin for ZBrush that helps you to get completely random variations of your current brush or alpha.
This way, it can help you to sculpt organic details in a way that is not predictable. So even with one single alpha, all the strokes will look different, as happens in nature.

It is useful when sculpting models like stone, skin, bark, ground, and many other organic features.
A must have for organic sculpting with ZBrush!