Did you know that replaying someone's words with a fraction-of-a-second delay short-circuits our brains so we can't speak? I didn't until I read this post on the the Physics arXiv Blog about how some scientists in Japan are using that quirk to develop "a speech-jamming device that forces recalcitrant speakers into submission." The blog also notes that it will come in especially handy at meetings.
And if you needed yet another reason to ensure your speakers aren't just reading off their PowerPoints, there's this little nugget: "Their tests also identify some curious phenomena. They say the gun is more effective when the delay varies in time and more effective against speech that involves reading aloud than against spontaneous monologue."
(Thanks to the Boston Globe for the link.)