Or cats, or house hippos, or just about any creature small enough to fit in one.
Alternatively, one can also use them to cover one's head to protect it from the elements. Many prominent historians, anthropologists and fashion designers believe this may have actually been their original intended function, but evidence are hard to come by in order to prove or disprove their theory.
In conclusion; that is an adorable picture.
Looks almost like something my soon to be sister-in-law would have done to her nails. Except, they aren't colourful enough.
Anyway, they are cool. And shiny...