This is a Red River hog at the Los Angeles Zoo. The zookeepers have hung a 5-gallon water bottle from the fence and the hog plays with it continually. Basically, he just knocks it around with his snout and seems to get endless joy from it. Kinda strange.

He dreams of being a percussionist.
Meooooow...if it feels good...keep doing it. Kitties know.
When I was a kid I had a Pennsy Pinkie. For anybody who doesn't remember them (which I assume is most folks, since I'm in my eighties), it was slightly smaller than a tennis ball and slightly lighter, with a smooth rubber surface instead of fuzz. It was used all around the USA to play stickball, step ball, wall ball, and who-knows-what-else.
I threw it against the back wall of my house at every conceivable angle, as hard as I could, and tried to catch it. I threw it against the front steps, which sometimes meant the point of a step and sometimes the flat, and tried to catch it. I drove my Mom crazy doing that, and I'm sure my parents thought it was kind of strange how I seemingly got endless joy out of such a simple, repetitive solitary game with no apparent objective.
I understand that hog perfectly.
you from Chicago? https://en.wikipedia.org/wiki/Pinners
My wife’s immediate reaction:
“Well, give him some more toys!”
Do the keepers do anything else for enrichment? Pigs are smart, he could be doing the equivalent of neurotically dribbling a basketball in the corner all day due to boredom.
This is what you are talking about: https://en.wikipedia.org/wiki/Stereotypy_(non-human) .
Wow. Thanks for the link. That's a lot to ponder.
Reminds me of the pitiful sight of a badger in a tiny glass cage at the zoo in DC decades ago when my family moved East (per my father; Mother & I recognized immediately that we were in the segregated south. That creature was obviously stir- crazy, turing in circles, & I was too young to be allowed to give a complaint - I felt guilty & homesick. That hog deserves better, too.
My German Shepard would endlessly try to herd a hard plastic ball around our backyard. She’d even herd my kids if given a chance.
OMG, what did you do to Charlie??
I don't know if you want the answer, but many mammals have scent glands on their cheeks, and boars initiate their sexy time by rubbing the sides of their snouts on their partners and lifting them with it.