Fractal walls

Caves are not straight lines unless they have been worked. Allowing for a point-and-click option when placing walls, would allow for not only diagonal walls, but also to expand this to fractal, textured walls to create realistic cave walls. Such an option should preferably include sliders (as for the terrain brushes) that allow you to select 1) how broken the lines should be and 2) how much the line deviates from true (the straight, diagonal line).