Proposed modes of operation: 'RoleyPoley': Roll or slide it around on the desk. Press down or bounce to click.

'Air 2-d': Fly up/down left/right to move, twist left/right to left/right click.

'Air 3-d': pop onto a plane to engage. twistie clicking. pull off the plane (or drop) to disengage.

'FreeRoll': roll to move. twisty clicking? or bounce/pop clicking?

Any can operate in absolute or relative mode.