Why do you need motion control?

Here are some examples of the kind of effects that can be achieved by using motion control systems:

Multipass background changing...............................................

<a href="http://www.youtube.com/v/FItlm_lIRK0" target="_blank">http://www.youtube.com/v/FItlm_lIRK0</a>
Stop motion animation............................................................http://www.theorphanage.com/ocp/ocp/qt_popup/5/1019/video_small
Time lapse, pan and tilt...........................................................http://viewfactorstudios.com/timelapse.mov
Multiplication of actors/objects..................................................http://viewfactorstudios.com/trucks.mov
Multiplication of Actors............................................................http://viewfactorstudios.com/muliperson.mov
Make objects appear and disappear..........................................http://viewfactorstudios.com/CAR_VANISH.mov
Two pass shot with compositing...............................................

<a href="http://www.youtube.com/v/lYeu56_RP4A" target="_blank">http://www.youtube.com/v/lYeu56_RP4A</a>