While reading the hot sauce thread last night, I was particularly amused when I ran acrossthis post. (You can see where this is going here.) So, anyways, yes, my secret talent is that I can vomit upon command.*
Ok, your turn.
*No, I’m not bulimic, nor am I advocating such activities. For two years I had severe nausea issues that caused me to toss my cookies almost every day. Do not try this at home. Void where prohibited.
I have the supernatural ability to hold a lit Bic lighter in my mouth for as long as I wish. This shocks friends and aquaintances who are, in the end, pleasently suprised that my breath then smells of roast (or burnt hair if I get too close to the mustache).
That and I can also vomit on demand.
Dude! We should start a club. 
In my late 40’s I developed not only a secret talent but an outright super power. I can actually suck the “cool” out of any situation, much like Iceman can draw the moisture from the air. Many people laugh when I tell them this, perhaps because I don’t wear cool outfits, and that is fine. I’m not trying to be cool. My kids know and fear the power and that is what’s important and their friends are learning too. Now in my 50’s my super power continues to grow.
As an example, should I decide that this vomiting on command trend needs to stop, all I have to do is post a video of myself vomiting on command on you-tube. A 52 year old (non-svelte) white guy is NOT something today’s whacky kids want to imitate. Fortunately for you all, I’ve always wanted to been able do this and haven’t learned how. Unless you count drinking 12 beers as “on command”.
I have an almost unerring ability to predict the losing side/romantic pairing in “shipper” debates. “Losing” being defined as not playing out in canon, and/or simply being unpopular in fandom.
I accomplsh this chiefly by simply noting what pairing I happen to like the best. Typically, the universe will react accordingly by sending the pairing down in flames.
Jargon esoteric enough for ya, sirs?
Oh, and I can dislocate my shoulders.
I can open my Eustachian Tubes voluntarily.
I can also vomit on command. Well, vomit a minute or two after command. I can also belch on command. So manly!
Oh yeah? Prove it!
I can do this too, but really, its a hard talent to show off.
All this belching and vomiting on demand - you lot must be a joy to be around!
I can do an imitation of dubbed movie dialogue, where my lips and mouth move in ways totally unrelated to what I’m saying. I can do this better than anybody else I have ever seen.
But I’m usually too shy to show anybody this super-power.
If you get someone to put their ear against yours, they will be able to hear that little soft, crunchy sound it makes. Honestly.
I can get people married. Seriously. All they have to do is break up with me, and the next person they go out with? Wham. Wedding. I’m also finding a corrolary that seems to imply that the messier the break-up, the better the wedding. I’m not sure it’s a skill I’d be proud to market, but hey, why mess with… Uhm… Success?
I can do this too; AND with that strangely deadpan voice they always used in 1970s Hong Kong Action Film dubbing. It’s a very useful secret talent. 
In addition to that, I can also do a very good Wildlife Documentary Voice (“The Shopping Mall is home to a wide variety of fauna; as we turn our attention towards the Food Court, we can see a number of common or garden variety Emo Kids, resplendent in their black skinny jeans and My Chemical Romance T-shirts…”) and my British Officer Voices, being either the Colonel-esque “RIGHT! STOP THAT! IT’S SILLY!” style, or the less commonly used (but also effective) RAF Fighter Command Briefing voice: "Gentlemen, our target for today is Le Havre; er, I mean a 15% increase on last year’s sales. There are enemy Ack-Ack positions located here, here, and here, and 462 Squadron are providing fighter cover on this one. Good Hunting, and watch for Refunds; HQ would like us to focus on that if we get a chance."
I can move my eyes independently of one another - I have to start from being cross-eyed, but I can move either eye out and back again while leaving the first stationary in the cross-eyed position. It isn’t exactly a sexy look, though, so I don’t do it much anymore. It was more fun as a kid to creep people out.
Is your name Chuck perhaps?
Good luck with that anyway! 
My superpower is the ability to have a piece of gum in my mouth, undetectable to the outside world, during any activity at all. Yes, *any *activity. Astounds the boyfriends, lemme tell you. 
But I always have minty fresh breath!
Is this where you, for lack of a better phrase, flex your inner ear and make that poppy-crackle sound? I tried explaining it and my boyfriend thought I was nuts. If this is what it is, awesome!
I can dislocate my shoulders and hips; it’s fun grossing people out but as I get older, they now hurt more and more in general. 
Helps with the vomiting power everyone seems to have.
Yes. It usually happens as part of the natural sequence of events when you yawn or swallow (which is why swallowing (or sucking a boiled sweet, causing you to swallow) helps when your ears are popping from pressure difference while aboard a plane, or driving up a mountain.
I can throw and catch a racquetball with one foot, using my monkey toes. (I have to be sitting down so I can turn my foot over in front of me, though)