I can do math in my head quickly and accurately. Something like 12 percent of 850, or 27 times 41.
There are certainly people who are much better at this kind of thing than I am, but I am better than the average Joe.
Getting ticked off quickly with my family.
Being misunderstood
Balancing sticks.
When I was a kid, I was supposed to sweep our long driveway. But I was really lazy, so I learned to balance the broom on my hand.
These days, I can balance brooms on my feet, hands, elbows, chin, nose, and forehead. I can toss a balanced broom in the air and catch it, still balanced, on the other hand. I can move it from finger to finger, or to and from my face.
If a stick is shorter, about the length of a baseball bat, I can balance it, toss it in the air so it flips, and catch it balanced on the other end. If it’s a tree branch with a curve to it, I can make it start spinning atop my hand.
It is the single most useless talent I have, and I’m better at it than just about anyone who doesn’t work in the circus.
I’m pretty good at math. Well over 100 published papers and an Erdos number of 2.
I’m pretty good at trivia myself. When I’m there, my pub trivia team tends to win. When I’m not, they tend to lose. I guess you could say I excel.
I’m good at a number of things, but I don’t know if I excel at them. Because that would require me to know how I rank compared to other people who are good at those things. And I just don’t know that.
Playing my baritone ukulele. I have my own style and it’s quite technical. Sort of a niche skill, though.
Pinball and Pac Man. Back in the arcade days crowds would gather 'round to watch me play.
I think that’s about it.
Oh wait, one more. Decades ago I was a supermarket cashier. This was back before scanners, when you had to enter each price manually. I was a wiz. Some regulars told me they always came to my line because they knew it would move the fastest. Others stared in disbelief at my flying fingers, sometimes demanding to see the receipt before paying.
mmm
Modesty.
Memory. I’m the go-to for the family for darned near any question. It’s kind of sad now in later years, because I remember original scenes and stories, and now the older folks report differently. Oh well.
I can 10-key sightless from either hand, either Qwerty or the reverse phone-style.
Professionally coding I guess. I have a lot of interests though and am fairly well read on a number of my hobbies. I have a lot of experience driving high horsepower performance cars too.
I am (or was, when I was working) exceptional at personnel management. I’m also very good at selling myself, and as a result of that, very good at selling things or ideas to others. The study of human behavior has always fascinated me.
Mediocrity?
That’s fortunate, because I excel at being an annoying grammar Nazi – in the broadest meaning of the term. I’ll criticize anything – grammar, spelling, punctuation, sentence structure, word choice, whatever, and I do it for free, whether the victim likes it or not. 
A semicolon? Really? Surely you meant “Yes, I do”!
I’m bad, bad, bad at everything except one thing. I can clean a goddamn closet like nobody else. Organize like no ones business. I’m kinda anal about closets and drawers.
Invite me over, I will change your life.
Compared to “most” people?
I’m much better at singing, writing, using big words, working with animals, organizing just about anything, editing, drawing, and designing or arranging things which require artistry. I am also a big fat know-it-all with an opinion about everything, usually a sour one. I bow to no one in the pessimism department.
On the other hand, except for those things I’m pretty awful at everything else.
Oh, I forgot, I’m also really bendy.
Lethargy and Procrastination.
Although I sure the ones who truly excel at these either don’t care enough to respond or just haven’t gotten around to it yet.
Photoshop, particularly image manipulation. Flipping a bic pen from a table and landing it flat exactly where it started. Estimating the overall time a bunch of things will take. Procrastinating down to the wire without consequence using that skill.
Nah.
I can recall faces and names from long ago. I guess I’m a super-recognizer.
And Machine Elf, I’ll claim that one, too — excellent motorcyclist. Over 200,000 miles without accident, and I’ve ridden through some really bad weather; heavy rains, snow, etc. Live to Ride, Ride to Live, as they say.