Here’s a pair of Portal-themed speakers that would flank your gaming PC. The red eyes would pulse to the audio of the music. In all likelihood these would be static speakers to avoid noisy motors, but if possible these guys would “dance” just like in the game (when they sang at the end of Portal 2).
Dave's Geeky Ideas 
When I saw the turret singing easter egg, I thought an audio visualizer would be awesome. This is equally awesome.
He would make for an excellent visualizer - or a subwoofer!