Placing a camera on the rotation axis creates the illusion of a anti gravity powers.
Here is how Justin describes the project over on Vimeo:
We built this set and tore it down for $350 in 1week. It was for a work project. It was a blast, we literally made it up as we built it. Practically everything was borrowed, the car rims, the casters, the furniture, the 5d, batteries, inverter, the fork lifts. We had a lot of fun playing with it once we got the shots
They started by building a cube frame, and walling it with wood panels
then the room was equipped with two wheels on opposing sides, and finally the room was painted, floored and furnished.
To “activate” the anti-gravity mechanism the entire room was lifted on two forklifts and rotated on the two wheels.