Metal folds

Recently we had some beer cans left over from a party. Might you fold from them?

You can, as seen from the pictures. It is not easy. You have about 1 attempt to make a fold. Folding back and forth once, and the metal will break. So any idea of flapping birds is defunct.

Boats and airplanes are possible. The boat is even water and acid resistant (they can, after alle, contain coca-cola...).

Jumping frogs are also possible, even in a version not so good in paper.