This is the SpeechJammer, a device that, when pointed at a person talking, will make them STFU up by playing whatever they're saying back to them loudly and at a few hundred millisecond delay, which apparently your brain can't handle. *drooling on myself* HERPA DERP?
The SpeechJammer, developed at the National Institute of Advanced Industrial Science and Technology in Japan, works because when we speak, we aren't just using our mouths as an "audio out" speaker. We actively listen to what we're saying, and the way we sound dictates how we proceed with our speech. The SpeechJammer screws with that. The "gun" shoots your words back to you, but with a delay of a few hundred milliseconds, which is enough to mess up natural cadence. The effect is called Delayed Auditory Feedback.
Admittedly, I thought ALL guns could make people stop talking. Plus start emptying their pockets. But what do I know? I'm just a man on the run from the law that rides a motorcycle and has beautiful hair and should probably have a movie made about him. HAHA -- YOU'LL NEVER CATCH ME, COPPERS! *revs bike, crashes over curb into apartment landscaping*
Thanks to Beatty and daniel, who agree they should employ these things in movie theaters. "But that would ruin the experience." I WANT TALKERS TO PUKE THEIR F***ING GUTS OUT.