Years teach us more than books.
Given a 3D input device and a display screen, how can we use the data from the device and the knowledge we already have to create a natural 3D interface where we can interact effectively with a virtual 3D model?
The way I did it..
.. was using the Razer Hydra controller with a virtual magnetic force to control the interaction!
p/s:Feel free to ask if you want to know more about it.