That sounds like a lot of presses on the L0 key ...
If you don't want that, then ... well... a light is cool. It would also be cool to have a latching switch.
Hey man, I agree you can certainly find better Use for those indicator lights..
But as to the Indicator of "What"... that is the issue we should iron out.
I think it would be nice as an aesthetic light show.
perhaps, make it do Hello world in binary when You plug in the USB cord.
Or, use an led to light up every time you type a letter
Or, use an led to mirror the network/ harddrive access leds, the same ones on your mobo..
^^ this part would be quite the challenge