I'm not sure if it's at all possible, but a feature I would absolutely love to see is a lighting effect that essentially acts as an audio visualizer for whatever sounds are playing on the PC.
Someone apparently achieved this here: [ame]
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But I don't like the hassle of having that program running as well just to achieve an effect I can't customize to my liking anyway.
Something else I'd like to see is the colors on the keyboard dynamically based off of what's on screen. I can imagine that would be very cpu taxing however, so I would understand this not being feasible.