As for your first paragraph, I think anything can be art. Tying my shoes, wind blowing through trees on my outside walks, any sort of light falling on any sort of every day object in just the right way... I'll stop, amazed and say to myself: wow.
As for your second paragraph: first day Aunt Flow has visited me (yes, strange thing for a guy to say). My mind is mush, and I am leaving in near future for caffeine, unhealthy amounts of sugar, and hamburger meat. Is it alright if I get back to you about this til mind is working clearly again?
For right now, only thing I can think to say is abstract expressionism, futurism, de kooning, paul klee et al, a tiny bit of basquiat, some amazing street art, some kick ass performance art, but that was mostly pre 21st century, and may not be modern enough for you. I'll look, however, and try to find more present-day examples.