Does it have to be from a square? This topic lends itself to box pleating, which lends itself to rectangles. I'd prefer the freedom of a rectangle. And what's the rule on multiple designs?
Rectangles are fine
I also dont mind multiple entries, just choose your favorite for the voting later on.
Nice vans, I still have no idea what to design ,but you already have two models
I made a ute. From a 21cm square, 24x24 boxpleated. The paper doesn't show it, but the wheels are from one side of the paper, everything else is from the other side (i.e. the wheels are a different colour to everything else). Ute by Folderp, on Flickr Ute by Folderp, on Flickr
Unless I make something better this is my entry for voting. I'll take better pictures soon.