Inception's rotating hallway was a real set

A closer look

When you have a blank check from Warner Brothers, you don't just use a green screen like a peasant. Nolan despises CGI so much that he demanded his crew construct a 100-foot-long hotel corridor inside a giant steel centrifuge that rotated 360 degrees. Joseph Gordon-Levitt had to learn how to actively fight stuntmen while fighting gravity, resulting in the most expensive and exhausting hamster wheel ever constructed for cinema.