An entire day of quiet sounds like heaven to me! I actuallyknow a woman who does this once a month. She has explained this to her family, friends and co-workers, and on her designated 'no speak' day she wears a button which reads "Today is my quiet day," to remind others why she's not talking to them.
With a tween in the house, and a college-age daughter who calls several times a day, this looks tough. I can perhaps make it for a few hours today only because the tween is in another state visiting her grandmother, and the older one will sleep till noon.
Let the quiet begin!