This a facial setup with interface.

The model have a synoptic view to.

 In this effects, I only animate the red ball. The other balls follow the leader, changuer its position and velocity acoording with the red one. The track is compositing using FXTree, therefore, change only the red ball you can make differents effects.

This plugin allows mouse gestures on XSI.

With this tools, you can execute actions or scripts moving the mouse. The scripts arec ontextuals, differents objects can execute different actions with the same gesture. 

It has three gestures levels (object, model and scene), this allow us to create an "mouse synoptic" behavior.

Making a rig,iI need a flexible tube with modicable extrems. With this tools you can control the tension and curvature in each extrem and in each axis.