I was in Ulta today looking at nail polish and one of the SA's informed that when you spend $15 (which is 2 bottles, they are $7.50 each) on OPI nail polish you get one OPI nail polish for free, you get to choose from 3 limited edition holiday colors. Not sure if there is a limit on this, they let me buy 2 different sets, so I got 2 free. This is an in-store offer only.