Bubbles

Soap bubbles are essentially extremely thin films of soap that has escaped and they are so lightweight they can travel because of their circular shape. Soap bubbbles are the physical structure of the math equation "minimal surface". They will take the shape with the least possible surface area possible containing a given volume. Bubbles have magnificent physics, they can easily merge with several other bubbles forming differnt shapes and not break. When two or more bubbles meet they will sort themselves by rearranging the largest in the middle and the lighter ones to the outside along their walls. Certain bubbles that touch a surface that is below freezing will eventually crumble as the air diffuses out and the bubble loses its form.

Pictured above: You can see that thin films of the soap that are left over are beginning to form thousands of bubbles of all different sizes, some are about to have enough volume with low surface area that they will be able to soon move around on their own.