What hardly-special, mundane things can you NOT do that it seems everyone else can?
For me, I can’t whistle. Never could.
I’ve just recently started to learn to swallow pills.
I can’t spell simple words in my head. I still can’t. Grammar, coffee, balloon. I know they’re right how I’ve typed them.
Ack! I saw the thread title and before it even opened I thought of whistling.
I’ve never been able to whistle either. Actually, I surpised myself a few years ago when I made the closest sound I’ve ever come to a whistle – and I wasn’t even trying.
Also, I can’t keep a plant alive. Everyone in my office stops by to comment on the beautiful greenery on my desk. Alas, I haven’t the heart to tell them it’s plastic.
I can’t reach anything above the first shelf in my cabinets.
Skiing… it seems like everyone I know can ski or rollerblade or whatever but I cannot keep my balance once gravity kicks in. Funny thing is I can cross-country ski and rollerblade at the rink perfectly fine.
I absolutely CANNOT keep plants alive. I have a black thumb of gardening death.
I can’t roll my tongue (the thing where you lift the sides of your tongue up to make a U shape).
I also couldn’t whistle for a long time. In the past year or two I’ve learned how to whistle enough to call the pets, and that’s about it. No show tunes or anything.
I can’t fly, even with the cape.
I can’t spit or burp on command. That was a major hindrance in 5th grade society.
I thought of whistling immediately I saw the title as well.
Roll-the-tongue is another one (it’s a well-known genetic marker)
Blow up balloons
I am embarressed to admit I cannot ride a push bike. I didn’t learn as a kid, and at various times as an adult I have tried, and wobbled around in a very scary fashion. I am resigned to spending the rest of my life on four wheels, which I feel is a shame. I can’t quite bring myself to look into full sized tricycles as a few elderly people in my area ride, maybe in another 20yrs.
Needless to say I can’t ski or roller blade either, or roll up my tongue, but I can whistle!
The trilling tongue thing for Rs in Spanish stuff. And I’ve been speaking Spanish for years.
Keep an SO for more than 2 yrs. 3 yrs max, usually 'bout 6 - 8 mos
Ride a motorbike. Had a bad wreck over 10 yrs ago, and now I’m spooked. Still.
Spell.
I can’t spell for shit. (thank goodness for spellchecker!)
I can’t make a straight or accurate cut with just about any saw. Even if I measure twice and mark with a line.
I CAN teach anybody to ski, so come on down Obsidion
What worries me is that half the world’s population is below average
I can’t roll my r’s, spanish-style. I wish I could.
[minutes pass]
Well, I thought I hit the submit button but I didn’t. Now I see NoClueBoy has beaten me, so I guess my new answer is that I apparently can’t successfully post to this thread on the first try. 
Thanks for reminding me about a scene in The Fiery Cross… I really should reread that one, since it’s been about a year or so.
As for what I can’t do… ooh, loads of things:
[ul]
[li]ski / snowboard[/li][li]whistle[/li][li]snap my fingers[/li][li]bake / cook with any degree of competency[/li][li]draw or do just about anything artistic (all my crafts end up looking like some klutzy kid did them)[/li][li]skip rope and do lots of sporty things[/li][li]plus loads more stuff, I’m sure…[/li][/ul]
Luckily, I can spell… most of the time.
F_X
I can’t roll my "r"s, either.
shyly looks at the floor
I can’t tie by shoes the “adult” way. I never learned how. It’s the two-earred bunny for me or nothin’.
walks away in shame
drive a stick shift.
(I can, however, whistle, snap my fingers, and trill my r’s.)
i actually thought of mentioning that i can’t wistle in the ‘what can you do’ thread…
used to be able to until a car wreck when i was 16, got bells palsy (paralization of half your face, due to breaking the bone behind my ear where the nerve runs from your brain to your face).
i can’t draw.
i can’t cook a grilled cheese sandwich on an electric stove (i can cook lots of other stuff though).
i cannot pronounce connecticut, where my grammy used to live.
i cannot french braid my own hair, but i can braid someone else’s.
I can’t crochet. I can’t ‘thread’ a sewing machine. I can’t curl my tongue (what’s this ‘genetic marker’ thing of which you speak?) I can’t do tumble-turns in the swimming pool.
But I can whistle and burp on command. 
I cant whistle either, well I can but not properly, I cannot roll my tongue or curve it or whatever you’re suposed to do to whistle correctly.
Can’t keep from saying whatever pops into my head…
I can’t roll, or curl, my tongue either. And what we mean, kambuckta, is that being able to do so is genetic. Either you can, ro you can’t. If you genetically can’t, then no amount ofpractice will change that. Technically, we are in a minority. We should get scholarships…
I also can’t draw or sculpt or carve worth crap. My stuff looks like a five year old did it. And a pretty talentless five year old at that.
I can, however, roll my r’s. I heard that is also genetic, someone correct me if I’m wrong. I can also whistle…not just whistle, but whistle by blowing out AND by sucking in. I can whistle for an indefinite period of time…so THERE!