LogInAn outstanding tool presented by Pablo Dobarro.
The brush has a custom cloth solver than can be used within sculpt mode in real-time on localized areas of the mesh. It allows controlling the cloth material by grabbing, dragging or pinching the surface.
The goodie is based on a simple physics solver that manages to give amazing results and the thing is that this ability is amazing even you compare it to tools like ZBrush where you have all kinds of brushes. The brush is said to feature four deformation modes that control how the forces are created.
"The brush can create the constraints only on the required PBVH nodes, so it should be easy to isolate the simulation on high poly meshes," notes its page. "As long as the brush size is not too big it should be possible to keep it real-time."
You can learn more about the brush here.