Hi, Andy here, first post..
I got an Arduino last year and have had hopes of recreating it using processing and an Arduino.. Its basically three LEDs which flash along with the music, not a VU meter, but a kind of EQ analyser. Hi, Mid, Low frequency..
I made a processing sketch which sampled an mp3 and included adjustable filters.
If one fancies a gander, the write-up is --> http://andycbriggs.wordpress.com/2012/04/12/forward-fast-mo-fo-fourier-transform-disco-leds/
And compulsory sensory pleasing youtube video...
Thanks for reading! Andy x