i remember this contest, as a newbie this is my first kind of contest i participated in and it was awesome with some great reward. thanks @gogogadgetupvote for bringing it back.

what you dont know;

Do you know that charcoal powder is the best mirror wiper ever?
take a few solid charcoal, grind it to turn to powder charcoal, take a dry small towel then wipe your dirty mirror firmly with it and see magic.
i learn't this method when i was an apprentice in the local barber shop in my hood.