plus those things drain the hell out of your battery life.
(not entirely sure if you mean a backlight or the lamp accessory). but, you could always mod the plug-in light from an incandescent bulb to a LED, and draw less current. like what people did to the nuby lights. LEDs look better anyways. i have no clue what the plug in things even have in them, there is one out there shaped like a blob monster though.
Why not just use the lamp accessory that plugs into the link-cable port?
Arduinoboy, LSDJ keyboard, gameboy link, stuff like that.
Started using nubys myself, this way I can find any playable DMG and just go
My Nuby scratches the hell out of my DMGs when I slide them on/off.