Interesting take, but I can't see much use for it perhaps. I'd probably prefer vertical scrolling, and to be frank I did something like this a long time ago by setting my Xorg screen settings to be larger than my monitor (and then scrolling around with the mouse). Tie that with a tiling window manager like awesomeWM so that you can configure while you work and it should work out to be just about the same experience.

Highly appreciative of people trying new things though, I will never shut down people's desire to experiment. More power to them I say, one day someone might stumble into something that really really works wonders.

edit: sorry, I thought the project WAS PaperWM. but no it's cardboard that has been inspired by PaperWM.