What are jiggle deformers?
 
 
 

Jiggle deformers let you cause points on a surface or curve to shake as they move, speed up, or slow down.

For instance, you can create effects such as:

You can apply jiggle to specific points or to the entire object. In the context of jiggle deformers, the term points means CVs, lattice points, or the vertices of polygonal or subdivision surfaces.

A useful technique is to apply jiggle to an influence object that underlies and alters the skin.

Be aware that you can create two or more jiggle deformers on different points of a single object. You can get the same effect more simply by applying a single jiggle deformer to the points and adjusting the jiggle weights. See Adjusting jiggle weight by painting.