How cool is this? It LOOKS like one of those click-clack inertia pendulum things...

[MiddleFingerMom]

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...but these pendulums go from side-to-side without any contact and the string lengths go from short-to-long.
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The first video is from the side and above.
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The second is shot from the long end and at about the height of the balls. It's by far the cooler of the two
(IMneverHO), but watching the other first helps you to understand exactly what you're seeing in the second one.
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#1. http://www.youtube.com/watch?v=yIkyPFLkNCQ
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#2. http://www.youtube.com/watch?v=yVkdfJ9PkRQ
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[pokerfan]

1. saw it here first

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=105x9684623

but it didn't have the view from above.

[MiddleFingerMom]

2. I missed that -- and the 8th reply had the view from above. n/t

[Angry Dragon]

3. repeat

[solara]

4. Wow what does it all mean???