http://ehacked.com/front_page/articles/make_your_own_vagina_vagina_origami/It's a pity I don't have dollars.
A dollarbill has an interesting size. It is a square + an A-format. If you take a piece of paper in an A-format (e.g A4) and cut it so it is a square then the rest you cutted off is the same as a dollarbill.