Does anyone know of any Chinese service that sends or publishes a regular A Word A Day for native Chinese speakers to expand their own vocabulary? I'm having trouble finding one, even though these are really easy to find for English (e.g. Merriam-Webster, Oxford English Dictionary).
you may try the international encoded han chinese and variants database (國際電腦漢字及異體字知識庫)
actually, it's "one han chinese character a day" service, in traditional srcipt; they even have an android app :)
have fun :)