Swallowed a Fly

Somehow, a fly, or a winged insect, gets into a character's mouth, sometimes by the character moving very fast. Hilarity Ensues in many different ways, usually after gagging. Bonus points if someone convinces the swallower that they'll die because of it.

Classical Mythology

 * In Greek Mythology, Zeus swallows Metis after she transforms into a fly. Cranial pregnancy ensues.

Film
"River Tam: "I swallowed a bug.""
 * The infamous outtake of Marlon Brando complaining about swallowing a fly while filming Apocalypse Now.
 * Happens on one of the Hilarious Outtakes in A Bugs Life. A bug swallows another bug. Wrap you head around that.
 * Considering that larger species of insects and spiders do feed on smaller invertebrates, this isn't really surprising that a stick insect (which can grow to be several inches long) could accidentally get a tiny gnat stuck in his throat.
 * In the Firefly movie Serenity, after a horrific encounter with The Reavers, the crew barely makes it back, and crashes the runabout back onto Serenity. Simon Tam (who stayed behind) is frantic over River, who is oddly calm:


 * Belloq in the last few minutes of Raiders of the Lost Ark is clearly seen to have a fly crawling across his face and into his mouth.
 * The Incredibles: when Dash runs into the swarm of bugs, one apparently gets in his mouth and he gags and spits it out.

Live Action TV

 * On WKRP in Cincinnati, Les rode a motor scooter to work, and occasionally had the problem of bugs in his teeth.

Songs

 * I know an old Lady who swallowed a fly but I don't know why she swallowed the fly...
 * Vocaloid Kaito did this in I Wish They'd Just Die (Shineba ii Noni)

Video Games

 * In Full Throttle, Ben chats with his old biker gang leader, Father Torque, while they're both in the middle of riding. Exhausting all conversation trees will cause Torque to say that he can't talk anymore because he's eating too many bugs.

Web Comics

 * This strip from The Oatmeal
 * In Goblins, goblin children are named by the tribe's fortune teller, based on a prediction. One tribe with a particularly inept fortune teller (and even more inept scribes) has a member named Stop The Ceremony I Swallowed A Bug.
 * The Serenity example is referenced in this Xkcd strip.

Web Original

 * The Homestar Runner cartoon "Bug In Mouth Disease" features Homestar distraught because he accidentally swallowed a bug. "The good times are over!"

Western Animation
""How do I land this--Ackk! Bug! BUG! That was a BUG!""
 * One episode of Ed, Edd n Eddy had Eddy unintentionally swallowing a fly and lost his voice because of it.
 * The SpongeBob SquarePants episode "Nasty Patty" had the health inspector swallow a fly before he could take a bite of the 'Nasty Patty' that Spongebob and Mr. Krabs fixed up, thinking he was an imposter..
 * From Avatar: The Last Airbender "The Northern Air Temple", when Katara tries out a glider:

Real Life

 * Truth in Television: notice the bugs on your windshield? It's very possible to have bugs collide with you at high speeds. If you don't have any protection and are currently talking or yawning or such, well...
 * Meta example: one stock snark to someone who's either talking too much or has their jaw dropped in amazement is "Close your mouth before you start catching flies".