On www.julianopie.com I wanted full screen flash to get that fully immersive flash experience. This is fairly simple to achieve with SWFObject, but there are a few IE gotchas.
Depending on how you want to do it there are a few CSS options. What I wanted to do was get the flash object to take over the whole browser and remove any other div, I also wanted to remove the scrollbars. Any scaling and scrolling I would do within the flash.