Oprah publicly endorsed the Lafco soap set on her new "Favorite Things" list -- which she releases every year -- and according to a rep for Lafco, invoices have nearly quadrupled since the list came out.

We called to ask if sales have increased dramatically since Oprah's endorsement, and the rep tells us, "Holy hell, yes it has. It is our third time being chosen. We're busy as hell."

The rep adds, "We usually invoice 80-100 a day, and yesterday we had 431 invoices."

As for the other products on the list -- they're also experiencing sales booms.

The makers of Corkcicle -- a wine-chilling cork -- tell us they've experienced a 350% sales increase ... and the people behind the Tusk Capri Checkbook Clutch say they're getting TEN TIMES the normal order amount.