Float and go through a door

From Glitches

From the game Super Paper Mario for the Nintendo Wii.

In 5-3, In the big cave where the power star is, look for a door next to a small ledge. Stand on that ledge and get close to the door without falling off. It's easy with Bowser. Enter the door, and you should walk into thin air and go right through the top of the door.

Submitted by: Dremo