I loved this:

(From the blog) And I recall bed sheets over mirrors in rooms where some tired soul had just given up the ghost. Nobody wants to be haunted forever, not even by somebody they once loved, and so they cover up the mirror so the spirit won’t see themselves and linger around. Ain’t a’ one of us needs a specter in the house. That’s why Sister Brown paints her ceiling haint blue. You just never know and can never be too sure. Some folks don’t know when to leave, even after they’re dead. And the horseshoe hanging upright above the front door won’t do a thing for the spirits, but at least your luck won’t ever run out.

More at The Last of the Grannie Witches