Nintendo.

On the list.

"So let's see - this frontlight set me back $30 in a low quantity order from a third party. Nintendo could easily order a huge batch of these for less than $5 a unit. The GBA's battery life with a front light will still probably hit the 8-10 hour mark, and the addition of the frontlight does not make the system any more delicate than it already is. And if you are willing to believe my testimony, the frontlight does not degrade the LCD's image quality when you compare it against a GBA in all but the most efficient lighting arrangements (i.e. a well-positioned lamp or a window with sunlight pouring in)."
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