Hillary tries this on Sergeant Kruger but he's too fast for her.
Marty McFly used this against several generations of Tannens throughout the Back to the Future trilogy. It only failed once, with Griff in 2015. He did turn and look, but was still able to block Marty's punch.
For example, in Part II, just as Biff was about to kill Marty, Marty says, "Well Biff, you're forgetting one thing. WHAT THE HELL IS THAT?" Biff falls for it.
Whenever Marty is required to distract ANYONE in the 2010 Back to the Future video game by Telltale, he'll ALWAYS use this phrase.
Jijii from Ichi the Killer manages to disarm and kill Takayama after the latter proclaims "Ichi isn't here to help you, now." and Jijii nonchalantly replies "What do you mean? He's right behind you," then swiftly takes advantage of Takayama nervously looking over his shoulder.
Like pretty much everything else, Bill & Ted's Excellent Adventure took this to ludicrous extremes: Bill shouted "Look, it's the Goodyear Blimp!" in a Wild West town. They fall for it, of course, but the funnier part is that the heroes are dense enough to try it in the first place.
In Hudson Hawk, George Kaplan tried to use this on Eddie (HH's real name). Kaplan: "Good God! What's that?" Hawk: "You don't expect me to fall for that old gag." Kaplan: "Shucks, I guess not." Eddie is then knocked unconscious.
In the original Buffy the Vampire Slayer, the character of Pike escapes from some none-too-bright vampires by pointing and saying "Look! Air!"
James Bond pulls this off in Casino Royale: While struggling over a knife with one of the bad guys, Bond glances over his shoulder, and the distraction is enough for him to wrest control of the knife and kill the bad guy.
Speed plays a similar beat, with Traven and Payne on top of a speeding subway train. Traven ducks, Payne gets his head knocked off.
Fletch: The title character stumbles on an Angry Guard Dog while snooping around a construction site at night. He distracts the beast by shouting, "Look, defenseless babies!"
Land of the Dead: Thinking that Cholo is about to destroy Fiddler's Green, Kaufman tries to get himself (and millions of dollars in duffel bags) to safety. An associate questions the bags. Kaufman shouts 'get down' and shoves the poor guy down, shooting him in the head seconds after. And what happens just as Kaufman goes to holster the gun? Why, Riley calls and tells him that Cholo's been captured.
Associate: "What's the bags?"
Associate: "Who's money?"
Kaufman: "Watch out! Get down, quick! "
Kaufman: "Our money."
Used in Dogma where the anti-abortion protesters are distracted, "Holy shit, it's the Pope!".
In Finding Nemo, Marlin tells Dory, "Look! A shiny thing!" Somewhat of a subversion in that he wanted her to come with him, but it effectively distracted her from her insistence that they should go through the big scary crevasse instead of through the clear blue water over the top with all the jellyfish.
They Call Me Bruce parodies the When You Snatch the Pebble scene in Kung Fu with this. Bruce, challenged to do the same trick by his father, replies that there's a large bird hovering over him. His father laughs at the idea that he could fooled by such a simple trick, whereupon said bird promptly poops on his head, enabling Bruce to snatch away the stone.
During Rebecca's job interview with Luke in Confessions of a Shopaholic, she shouts "What's that behind you?!" to distract him from asking further questions about her knowing Finnish (which, of course, she lied about on her resume).
Buzz: You're mocking me, aren't you? Woody: Oh, no, no, no no... (points) Buzz look, an alien! Buzz:(spins) Where?! Woody proceeds to laugh at Buzz
Disney Adventuresdid something very similar in one of the April Fools' Day editions. Woody basically shouts to Buzz "Buzz, look! It's the evil Emperor Zurg!", Buzz turns around and shouts "Where?!", and Woody says "April Fools!"
In Bolt, Mittens tries to threaten Bolt into letting her go with a Styrofoam packing peanut (Bolt has become convinced Styrofoam is what made him lose his "powers"). Bolt distracts Mittens long enough to disarm her by looking over her shoulder and saying "...That's a weird place to put a piano."
Beetlejuice: While sitting in the afterlife waiting room with a witch doctor, Beetlejuice says "There goes Elvis! Yo, King!" When the witch doctor turns to look, Beetlejuice snatches his number so he can go next. What makes the gag even funnier is that there are literally millions of dead souls in the waiting room, and Beetlejuice's number that he wants to switch has an absurd number of digits in it.
Then the unvoiced variant comes into play when Indy frantically scrambles to get away from the spinning plane propeller. Said mook doesn't get the hint until it's already too late.
The Guns of Navarone: When Brown confronts a German sailor on the small boat, the sailor tries this on him. It only works for a moment, then Brown knifes him.
Up The Creek: After Bob McGraw (Tim Matheson) is caught in a girl's hotel room by her (ex)boyfriend & the boyfriend's sidekick, he uses this. "Look the Goodyear Blimp." They look. "Smart, real smart"
Up had Russell shouting "Squirrel" when about to be gunned down by several dogs, exploiting the dog's weaknesses about squirrels earlier. The dogs easily fall for the trick. Not only does Russell escape unharmed, but the dogs are so focused on trying to attack the squirrel they ended up shooting each other down.
In A Bug's Life Francis flies up to P.T. Flea and shouts, "Hey, P.T.! Look! Money!" P.T. instantly turns, and is webbed up by Rosie. This was a little redundant, as it wasn't really much use as a distraction; the trick could have been pulled without the line. But it was damn funny.
The main character of The Invention of Lying, being literally the only person in the world capable of telling a lie, uses this to cheat at roulette in a casino.
Specifically, he shouts "look at that unusual thing!" and everyone in the casino does.
In Murder Ahoy, the villain has disarmed Miss Marple while her friend Mr. Stringer has gone off on an errand. Just as the villain is about to kill her, she suddenly looks past him and she speaks to Mr. Stringer as if he is standing right behind the villain. This is the cue for the villain to turn around and look, but instead of doing so he smugly tells Mrs. Marple that he isn't going to fall for THAT old trick ... whereupon he gets hit over the head by Mr. Stringer, who really IS standing behind him.
The trope is also used in Batman Begins... kind of. When a criminal ambushes Rachel Dawes, she threatens him with using her tazer (which she always carries around with her for some reason). The criminal then flees, although not because she was carrying a tazer, contrary to what she thought: He fled because his partner in crime who stalked her off the train (presumably as some sort of hit job for Falcone) is ambushed by Batman and then beaten down. Rachel then turns around after gloating a bit just in time to see Batman, and instinctively shoots the tazer at him only for it to have little, if any, effect. Luckily, Batman just happened to be on her side, supplying her with incriminating photos of a Judge to blackmail him into essentially giving Falcone imprisonment.
Used when The Lorax first encounters the Once-ler:
Lorax: Did you chop down this tree? Once-ler: Uh, no... Who did it? (gasps) What's that? (points) The Lorax looks away. The Once-ler drops his axe on a small barbaloot. Once-ler: I think he did it.
A variation occurred in Return of the Jedi: During the battle above the Sarlacc Pit, Chewbacca attempts to warn Han Solo that Boba Fett is nearby and aiming at Luke. Han Solo (who is temporarily blind due to the events of his undergoing freezing in a block of Carbonite in the previous film) panics and asks where Boba Fett is and turns around. He then (accidentally) activates Boba Fett's jetpack while turning around in a frenzy with his pole, resulting in Boba Fett flying smack into the side of Jabba's barge and right into the Sarlacc pit.