Using FibrMesh in ZBrush to easily create complex organic shapes like trees
The technique of this tutorial is rather simple once you know the steps. Once you have a good grasp of how the settings in FiberMesh affect the shape of the objects, you can create a wide range of things following the same process.
You can generate fairly convincing trees in a few minutes. Playing around with the settings of FiberMesh, you can also create very abstract objects that follow a similar pattern: