If you've been wanting to stock up on luxury mascara, today's the day to do it. For today only, Nordstrom is offering a "buy two, get another free" special on mascaras from a bevy of brands: Lancome, Dior, Estee Lauder, Clinique, Bobbi Brown, MAC, Chanel, and Yves Saint Laurent. Although you can't mix and match among brands, it's a great score if you're a fan of a certain mascara. The deal is good both in stores and online (the free mascara will be added to your cart automatically). So if you want to get in on the action, move fast, because this promotion will be over in the blink of an eye.