We know the Foo Fighters rock...now there is seismographic proof to corroborate our beliefs.  At a show in New Zealand, the Foos along with the 50,000+ in attendance caused the Earth to tremor and stuff.

Take it away scientific people:

The first vibrations were recorded around 7:30pm, part way through the Tenacious D set, but the biggest shakes started at 8:20pm when the Foo Fighters took the stage, and then it all went quiet at 11pm when the gig ended.
The concert vibrations were recorded as a semi continuous harmonic signal with a peak osculation of 3Hz,  ie the ground was shaking 3 times per second in a nice rhythmic motion.  There are lulls in the signal between the songs and peaks in signal intensity during the songs.

Yeah...what they said.