Music-sync'd Strobe effect in video
Trapcode's Sound Keys will do the job:
http://www.redgiantsoftware.com/products/all/trapcode-sound-keys/

From the promotional text:


  Now it's easy to synchronize motion and sound in After Effects. With
  Trapcode Sound Keys, your audio-intensive animations no longer require
  extensive keyframing. Visually select parts of an audio track and
  convert them into keyframes, syncing footage with audio using
  amplitude or frequency ranges. Sound Keys is applied as a regular VFX
  effect, so you can save its settings with your project, generate
  keyframes into output parameters, and link keyframes to expressions.
  The possibilities are huge, just like the beat.


By using the generated key frames you can hook them up to almost any effect or behavior that you want.

A basic example of using this plugin to drive a few "strobes":