This is an odd one.. it's called an "excuisite corpse drawing," and it was an assignemt I had to do for my art class.

It works like this:
It's folded up into four sections. I start at the very top, and I draw the head.. I then make little marks on the next section indicating where the neck ends. I apss it on to someone else, and they draw a body, but, they are not able to look at the head.

Thgis goes on for all 4 sections, a different person doing each different one. Then you unfold it, and see the entire thing, and, it usually looks really weird. Then you edit it by erasing and drawing some more with the pencil to give it a bit of flow, so it doesn't look all jumbly. (like in this one, his original hands only extended to his stomach area.) I added in the hook hand, football cannon, all the backgrounrd, etc. as well as color it all.

It's really fun, you should try it sometime if you have a lot of artsy friends!