In the past I had a darkslide that I cut down to a little over half and used it to make two panoramic images per 4X5 sheet. It does require turning the back and keeping track of what has been shot, but I enjoyed it. I have recently gotten back into 4X5 and think I might try that again. It is a bit of a workaround, but it is almost free if you happen to have a spare dark slide.