I can pick up different objects with chopsticks in both hands at the same time. Can also eat this way.

I didn't put any time into mastering this, though. I just gave it a try one day and found it to be easy.

I wouldn't say I've mastered it but with my current set up I am as good as I can get with macrophotography.

Whistling. Took decades and I can do it two different ways (lips and teeth). I now do it subconsciously when listening to music where I’ll typically add other melodies or harmonies. I can bird call pretty much flawlessly. Loudest I get is over 100dB. Average is low 90s. Not much use but it’s fun.

Whistle like a pidgeon and mourning doves

I can solve a 3x3 rubix cube in under 60 seconds.

Just practice and memorization, it’s not that hard.

I learned to open bottles using a lighter, and then taught my friends. After a while, we just started referring to lighters as “bottle openers”.

I can palm a tennis ball, roll it down my arm, bump launch it with my bicep, and catch it. Freaks people out who are standing close as the ball launches right at them, but I've always caught it. Discovered later I could do it with anything that rolls like a microphone.

I remember reading about a Pa Kua Chang master who could walk through a crowd with a full teacup and not spill any. For whatever reason I started to practice walking with a full to the brim teacup (with or without a handle) and now I can go up and down stairs with one or two and not spill anything. Usually

I used to be deadly accurate throwing a paper book of matches. A useless skill even when they were readily available.