I'd like to see a bird fly in one direction high up, decide it wants to go back the way it came, do a dive down loop flying upside down for a second
before doing a flip and continuing back the way it came
At an old Hangglider launch site there was a local crow that would repeatedly do back flips off of our windsock. Landing right back on it each time.
Sometimes birds fly just for the fun of it. So do I, lol
I've seen barn swallows do some rather impressive flying too. Mostly to catch insects, but sometimes they do crazy things to draw attention when
you're near their nesting site.