I heard somewhere that if every citizen of Japan were to jump up and down at exactly the same time, it would create a tidal wave that would hit the US. For some reason that image always made me laugh, but I didn't think someone would actually organize something similar. Great, now the US needs to build an anti-jumping-caused-earthquake shield of some kind to reduce the threat of rogue jumping caused earthquakes/tidal waves.
psst, we're all jumping tomorrow at noon. pass it on.