I can curl my tongue and flip it both ways, and also make it undulate in a wave. Some says the latter is gross, some say it is cool. For some reason, my childhood best friend and I cultivated this latter talent in response to the constant and repeated singing of "amber waves of grain".

I can move the toe next to the big one (the index toe) independently of the others.

I can pop my 3rd thumb knuckle. The one next to my wrist. Yes, that thing pops and it feels... awesome.

I can walk on my hands. This is not a trick of language. I can put my hands on the ground, put my feet in the air and walk.

I can put my palm over my eye socket and make fart noises.

I can duplicate many animal sounds , with my specialty being the exact series of noises that a cat makes before , during, and after the birth of a wet, abundant, hairball !

Scream loudly as my fingers dislocate.

All my digits can be bent backwards 90 degrees

I'm double jointed in all of my fingers and I can (this one's a bit gross) spray saliva from the salivary gland underneath my tongue on command.

My knees are missing cartilage that keep them from bending backwards. I can hyper extend my knees backwards some times this comes in handy when reaching gives me a few more inches. It is not painful at all.

I have very flexible toes, and can pick things up with them. I feel very untalented right now.

OK.... with 1 & 2, you should be able to "fart on command," too, ala Le Petomane.......

wiggle my ears, flare my nostrils, and raise & lower my eyebrows separately or individually. At the same time.
Oh, and I can pick up and throw tennis balls using only my toes.
EFFIN' A, Americas got talent!!!

I have some others, but backpage.com just got shut down, soooo......

I can clear my Eustachian tubes without moving any other muscle, can raise and lower my body temp, pulse, and blood pressure almost instantly. Body temp is more raising it, lowering is harder, but I can make the others go up and down.

I can make a very realistic cricket sound. It is loads of fun at a comedy club or when someone tells a bad joke.

I dropped a wooden pallet on my right foot decades ago so now I can make a loud clicking sound with my big toe.

All my fingers are double jointed..and I speak 5 languages and have a dry sense of humor..

My body isn’t really that amazing, it just functions sorta.

Haha wild .. Fair play .. I am like a mish mash of injuries and gaffa tape or glue after years of ahtletics and slightly mad mountain biking. Still being bendy but also recovering from car crash and mountain bike accident fractured elbow at mo. So a bit slow and it's pissing me off lol. Could always standardly get feet behind head as kid and thumbs bend back wrong way right up to adulthood. backflips and stuff. really good climber.. Three and two finger pull ups. would kill me now lol.. I can have a pretty large person still stand on my tummy while i lie down and jump up and down or stamp and it's just iron.. they get scared to whack it so hard .. i am just laughing. Never tried stepping through hand but if tried now with fractured arm would go into face lol. With you on the burping lmfao. I have bat ears lol. Can still free climb a 25 ft rope with hands alone in full hiking gear!

I can raise my left eyebrow like nobody's business. Does that count?