You always want what you can’t have — especially when it comes to beauty products. That’s why we’re getting the inside scoop from your favorite retailers on what’s selling out right now, how to sign up for waitlists, and where to go to find the next best thing. Because if everyone’s buying it, you know it’s got to be good.You know how slicking on a layer of red lipstick instantly makes you feel better? Well, in our opinion, dry shampoo has the same effect — but for our hair. It doesn't just refresh our strands, it boosts confidence (and volume) with every powdery spritz.But here's the thing: dry shampoo does so much more than simply soak up unwanted oil. We use dry shampoo to inject oomph into wayward strands, zhuzh and refresh a dull mid-day hairstyle, and even as a hair perfume.So, given this product's quasi-magical abilities, it didn't come as a surprise when we discovered that Living Proof's Perfect Hair Day Dry Shampoo is one of Birchbox's best sellers. The product has over 10,000 reviews on the retailer's site, many of which are glowing accounts of its oil-sopping abilities. (More on what makes it so special, here .)Itching to give this bottle a try? We don't blame you. But if the stock is wiped clean before you can commit, we've gathered four other A+ dry shampoos that will fulfill all your oil-absorbing and hair-zhuzhing needs. Check them out in the slides, ahead.