Inverted room

[MrBigzy]

Well, for one, you would have to convert the walls to entities with the model editor. And then to rotate the room, you would use RotatePropToSpeed, though you would have to do this for every wall/object not connected to another rotating object, and you would have to make sure they all have the same pivot point set, as well as the same angular velocity.

For stuff sticking to the walls, you can use AddAttachedPropToProp to connect entities.