How rearranging a bedroom relates to writing.

So the weekend we had to rearrange our bedroom to make room for a new desk. It got me thinking how much we rearrange our books before its finished.

We might move a character from a scene to make a better entrance later on, or to set up something later. We might also move a certain scene for more impact. In my current project I expect to move certain things around to make it better. How do you guys handle the rearranging of you book? I bet mystery writers do it more than others.

Are you guys like me and have a separate file for things to save field later? I use it to store things that don't fit yet but could work later on. What are some of you writing techniques for organizing your novel?