This sketch displays lyrics and flashes lights to the beats of the song "Byegone" by Volcano Choir. The beats are coded in via millisecond timings read from frequency-measuring audio software. Programming for beat frequency detection is an alternative to this method. The hardware setup includes an Arduino Uno, a breadboard, six LEDs, a 16x2 LCD, and a potentiometer (to control the contrast of the LCD).
Video of the lightshow in action: https://www.youtube.com/watch?v=iF-nj2SV1pM