
Maybe movie theaters are just being too polite. No matter how many times the friendly animated popcorn tells the audience to turn off its cellphones and pagers, few movies can go their entire length without someone’s “Big Pimpin’” ringtone blowing up in everyone’s face.
Instead of depending on the chides of talking concessions, theaters can now gain full control over the usage of cellphones with nothing more than a quick nanotech paint job. Taking sub-microscopic pipes called nanotubes and filling them with copper, a company called NaturalNano has developed a paint that is able to passively block specific radio frequencies. When teamed with a special filtering device that monitors RF signals from the outside world and transmits some or all of them into the blocked area, the paint provides a cost-effective way to fully control the radio traffic coming in and out of any room.
The possibilities are endless. Concert halls could choose to allow cellphone usage only during intermissions, schools could prevent students from cheating using text messages—all the while allowing emergency signals to pass through unaffected—and movies could be enjoyed sans Jay-Z interludes.
Guess the talking popcorn should start looking for a new gig. —John Mahoney

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The 6th annual Invention Awards are here, from an inflatable tourniquet to a better lobster trap to spring-loaded hocket skates. This issue is all about the celebration of invention.
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