What about reading while you're laying down? Like holding it above your face while laying down? Or even just sitting in a chair with your hand through the handle thing.
It works fine for that, it's nice and tight so you could swing it around and most likely not lose it lol. I've used it in bed the way your asking, it's more comfy to use in widescreen mode for me that way, but you can use it in portrait very easily.