I know it's a very simple mod, just the ol' window in the side with a light job, but I think it's pretty neat.
First couple with the light off, to try and bring out the window.
That didn't work, so I took the side off to take a photo of the window itself.
With the light on, window off...
The light control, it's a cold cathode with beat detection. I was actually quite disappointed as I needed to sit the subwoofer right inside my case (which is impossible) for this feature to function properly.
Also a couple of fans I have added (simple stuff)
Then with the window on, with light.
Finally my desk, complete with Q3 mouse pad :)