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From the question about sharp pods under airliner wings, I think the right term is anti-shock bodies, or flap actuators/track fairings.
What's the little antenna looking thing extending off the rear end of it? My best guess it something anti-static? Why are they necessary?
I should add that this is an American Airlines Airbus 321.
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You're very right. It's a static discharger or "static wick", and it is used to dissipate the static electricity accumulated during flight. The electrical buildup happens during flight through precipitation, clouds, dust, etc., and is known as "precipitation static".
Once the static reaches a certain point, it will discharge. Without wicks, this happens through antennae and can really mess with communications or navigation. Wicks make sure that process doesn't cause problems.
