100 Złoty Frog
Polish banknotes have 2:1 proportions, a square folded in half. This makes them good for adapting models folded from square paper. I came up with the idea of...
Money Folds
Money folding (with dollar bill origami being especially popular) is the technique of using paper money as folding material. Since the size of the bills and the properties of paper are set for any particular currency, in this case folding material affects the whole design. Creators also often try to use the patterns found on bills in their models so that they end up in particular parts of the finished design.
This page lists models of a single type. You might be interested in folding instructions instead.