So if you're one of those with a lovely mac 'puter which you love and cherish (me too), Do not be afraid. Love it. Cherish it. Feel free to also advertise something else with that soft glowing light on the front.
I did mine with a sticker, black permanent marker, x-acto-like knife, and black gaff tape. Works good. Though you consider laminating with clear packing tape or something after your done to preserve it from peeling up in places over time.