i'm surprised that so many people have issues with the lights. At my desk, between printers and drives and cell phones and power adapters, there are probably 15 different LEDs that blink or light up... looks like a damn christmas tree. I've rarely if ever noticed my iMac's pulsing light among these other ones... Of course, it helps that I have a home office separate from my bedroom.
As to the light being annoying at work... weird. PHd, man, you should scoff at such inconsequential things! hehe...
That said, i suppose it would be nice if someone came up with a 3rd party hack to change the lights... I just don't see Apple doing it, because they don't like to burden down preference panes with too many extra features. Plus they most likely want uniformity of the products that are being carried around the real world... The "breathing" light is starting to become symbolic of Apple, but it would seem more haphazardly if people could choose whether or not to see it.
Of course, if people are putting tape over the lights, it looks much more haphazard...
paul