Sorta. 
(I taught myself, so my technique is lousy, but I can stay afloat.)
I’m in grad school now, and I’ve been distressed to discover I can’t speak up in class without first rehearsing what I want to say in my head several times. I’m envious of those who can engage in lively debates in class, because by the time I know what I want to say, the conversation has turned to something else. If I have to speak without preparation, I’m an incoherent mess.
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This reminded me…I can sight-read music as fluently as I read words, but I cannot memorize music to save my life.
The two-fingered whistle and snapping my fingers. I guess I’m just no-good at attracting attention to myself.
Oh, and you can probably add cartwheels of any type to the list. I never tried as a kid (believe it or not) and I’m too old and stiff to even think about it now, dagnabbit!
Swallow carbonated beverages without holding them in my mouth for a few seconds. This is not an exaggeration of time; it’s about 3 to 4 full seconds. I think I need time for the fizziness to go away, or something.
It’s a good thing I don’t much care for those kinds of drinks, as I doubt it’s a great idea to bathe your teeth in them like that.
Do a running dive into a swimming pool. I can dive if I squat down and roll myself forward with my hands in front of me, but that run-jump-dive is beyond me.
I have never been able to:
[ul]
[li]do the two-fingered whistle (despite many times slobbering on my fingers trying)[/li][li]Turn a cartwheel (just can’t get my legs up enough)[/li][li]some simple math (if I think about it for longer than a second I won’t get it and will need a calculator, while breaking out in a cold sweat)[/li][/ul]
Let me add one for my husband - he cannot float in water (or in the air, either, but that’s not important right now). I know when most people hear that, they think, “Well, everyone can float a little; are you sure you’re doing it right?” I have worked with him extensively on this - the man is made of solid granite - he does not float AT ALL. Ever. If you put a scuba on him, he could go sit on the bottom of the pool until the air ran out.
I cannot tell a lie about my 45-foot yacht.
I CAN NOT switch gender pronouns in conversation. It’s a nightmare trying to say “He said that to her because he thinks his is better than hers.” I usually just give up and stick to one gender throughout, turning the minority gender into the other one. Rarely does this confuse, often does this amuse.
I cannot shuffle cards. My whole family can, but every time I try, I end up spraying cards all over the room.
As others said, I can’t shuffle cards, belch on command (unless I take a gulp of pop), or do the two-fingered whistle.
Other things? I can’t drive, I cannot do a proper dive into a swimming pool (at least not from a diving board-I can do the shallow dive thing). Oh, and I can’t sing, and I suck at math.
(Oh, and from what I heard, curling one’s tongue is a genetic thing. True?)
You can overcome it with finger exercises. My husband did; I almost have. I started using one of these things after I broke my third metacarpal in a car accident. Luckily my husband had one already around - it’s how he became able to move his pinky independently for guitar work.
I can’t distinguish among models of cars or trucks. I can tell a sedan from a pick-up, but all sedans looks the same to me, and all pick-ups, too.
I can do the two-fingered whistle with my thumb and index finger (hrm…guess that would be the thumb and finger whistle…) but I never mastered the no-fingered whistle, like you see cowboys doing when herding cattle.
I didn’t learn to swallow pills until I was in my early 20s.
Like others, I can’t drive a stick (never learned), I can’t do basic math in my head and while I did learn the multiplication tables in grade school, I’ve forgotten them over the years.
I have never been able to touch my toes without bending my knees, even when I was young and athletic.
I can’t pronounce ambulance or antibiotic as most people do, usually stressing the wrong syllable even when I try to get it right.
Drive a car.
Another “can’t finger whistle” guy.
Never realized so many people couldn’t do that. I feel better now.
All those with problems popping pills 
– what you have is a heightened Gag Reflex. This article purports to suggest a way of moderating it; in addition to the warnings within, I’ll add my own caveats that IANAD; I ran into this article doing a Google search and have no idea how accurate, safe or wise it is; don’t take medical advice from strangers, etc…
Well, it’s a little different when you live in Ireland, isn’t it?
Well there aren’t that many horse and traps going around anymore ya know!
Drive a car and tell cars apart.
I’m about as ignorant about cars as one can be in the 21st century.
Iron a shirt or pair of pants. I suppose it’s willful ignorance as much as anything else - I’ve never sat down and learned, but it seems hopelessly daunting to me.
But I can snap my fingers, whistle, gargle, swallow pills, roll my Rs, roll my tongue, speak articulately off the cuff, ride a bike, drive a stick shift and do a decent cartwheel (at least I could 40 pounds ago), so… 