This is not a pointless skill unless you are a woman and can do it to yourself and even then…
There are lots of things like that which I do and just consider normal but other people think are freaky.
I can pop my ears without the use of my hands. I cover my nose with my top lip. Beats licking your nose, anyway. 
I can suck my tongue to the back of my throat and vibrate it very quickly to make the most disgusting slurping sound.
I can also make a clicking noise without moving my teeth, lips, tongue, Adam’s apple, or ANYTHING - I’m not even sure what body part it comes from exactly.
I can store vast volumes of water in my cheeks. That’s how I drink - I store as much liquid as I can in them before swallowing it all in one gulp - and I can get quite a bit in there.
There’s also my walking, which isn’t so much a skill, but just a bizarre thing I do subconciously. I never walks to same way twice, and it ofen reflects my mental state. I once developed a limp for absolutely no reason when I didn’t want to be going to a class!
And finally, I know far, far, FAR too much about Doctor Who. I can often place someone’s memory of it within seconds. Whether or not I’ve seen the story myself.
I can hang spoons on various areas of my face. I do this in restaurants and embarrass my family.
Wow! I thought I was the only one! I learned how to whistle(?) like this first, before I learned how to normally, you got the hooting down but if you do it at the right angle you can get this REAL loud whistle
I can do the train doors thing, the picking things up with my feet thing, and the poison ivy thing – although I was later told that it’s an allergy that CAN be induced with cumulative exposure, so I no longer wade through it to show off like I did when I was young.
I don’t have any other great silly skills myself, but my sister has one that has ALWAYS annoyed me – she can, 100% of the time, draw a PERFECT horse on an Etch-A-Sketch.
Hi, I’m Nickel, I’m mostly ambidextrious, although really a lefty, and I can always find a way to open a beer bottle without spewing a drop.
i just played that and one of my cats is freaking out looking for the owl. 
i can do a perfect imitation of a howler monkey. :o
Nickel!
Welcome to the SDMB!
Give us your two cents worth about this place.
I can use chopsticks with both hands. I’m just starting to practice with the left, so I can’t eat rice well yet, but I can get every grain when using chopsticks with my right hand.
I can do this, too! But I’ve found that the only place on my face where I can get the spoon to really stick for a while is my nose. And I have to make sure that my nose isn’t too greasy. (I have oily skin.)
I can make a sound like water dripping from something. I’ve used it to drive annoying and/or rude people nuts. They keep wondering where the heck the leak is coming from.
I used to be able to recite the names of all the elements (old nomenclature, not new) and pi to 20 decimal places. But now I can’t.
I can’t imitate a dubbed film the way Revtim described (actually putting your mouth out if “sync” with the words.) However, I do a “dead-on” impersonation of the guy who has dubbed those films for decades. You know the guy - speaks in a very staccatto manner - “What can we do?” “Here comes Monster Zero !!” “We need Rodan and Godzilla to defend us !!”
Also, I can cut a deck of cards with one hand.
If you are wondering - yes my parents are very proud.
What can I do… I can pick stuff up with my feet and know who is calling. I also have this uncanny ability to fall so slowly I think I age before i hit the ground…
Um…AHA! I can wake up in the middle of the night in the dark, or just about any other time for that matter and without a clock be able to guess the time +/- 10 minutes.
“Grace”
HAHAHAHA… I meant “I can pick stuff up with my feet and know who is calling” as two different things… but hey that was 5 minutes and an entire nother drink ago.
“Grace”
My ability is subconsciously predicting when the alarm clock will go off, then waking up a few minutes beforehand. Whether the alarm is for 6 am or 9 am, I’ll wake up at around 5:50 or 8:50 respectively. I don’t think I’ve ever been woken up by an alarm clock (except when it was for my roommate and I didn’t have to get up), but setting the clock reassures me.
Not a silly skill, but it might count. I write upside down. I can do sideways as well, but I’m not so good at it. Useful when helping kids with their mathematics – I can be on the opposite side of the desk, I’m not right in their space, they can see what is happening because I’m not covering up anything with my hand as I write.
There is a common misconception that no one can place their heels against a wall and bend over and touch their toes.
Yet, I can do this. I am pretty limber and can bend over to the side and get around to press my chest against my knees.
I have won money at this. Takers?
I can fire saliva directly out of my saliva glands in a glorious jet up to a distance of 4 metres. When you do it at people, they always think it’s raining.
I REALLY want to hear more about singing two notes.
You can do this on command? If so, that’s quite a skill. I can shoot saliva out of my mouth in this way, but it just kind of happens sometimes, and I’d love to be able to control it.
Freiheit, about singing two notes at once: It’s a technique known as (harmonic) overtone singing, or throat singing. It’s a traditional form of singing from Tuva and Mongolia. Recently western singers have developed an interest for it. It involves singing a base note like you would normally and then accentuating one (or even more) of the natural overtones in the sound from your vocal chords with your tounge and lips.
I learned how to do it, but I’m at party-trick-level at best.
More info here or google ‘overtone singing’.