What is art?

Art is intentional manipulation of a medium to convey meaning (or a message) beyond utility. By "intentional manipulation" I don't mean a specific product of the efforts because sometimes art is the process, like a meditation. In some cultures, people spend hours a day creating a mandala (example shown), only to blow it all away at the end. For them, the end product, while often beautiful, complex, and full of meaning, is not the artistic part of art-making; instead, the art is in the meditation involved in spending that time creating the piece. In contrast, photographs or paintings are often purely "end result" art, appreciated almost solely for what is tangible at the end. Paintings are not often famous for their creator's mental process during the creation of the work; instead, they are famous for content, composition, and so forth.
Where art becomes confusing is in the utility it transcends. Can something still be art if it's usable? In class, one newspaper featured a print of a barn. A napkin circulated with it on which a similar barn was printed. If illustrations of barns can be art sold for millions, is it still art on a napkin? If it was the exact same picture, would it be art on the napkin, or merely decoration? If the Mona Lisa was printed on underwear, is that still decoration or does it become desecration of art? Or is art just decoration?
I would say that all art contains the capacity to be just decoration, but all decorations are certainly not art because decoration is not meaningful manipulation (more about status).
Are movie graphics art? Is the flag art? Is porn art? Are company logos art? ...Hmm.