When it comes to beauty products, all the media hype in the world means nothing without the GSA—the Girlfriend Stamp of Approval (you know, the uncontrollable need to tell all your friends about an amazing discovery). It’s even sweeter, of course, when you GSA a product you weren’t expecting to love, as has been the case with one of my newest favorites, SkinCeuticals Hydrating B5 Gel. A notoriously heavy-handed gal who zips through gallon bottles of shampoo and lotion (and has never quite grasped the concept that a little goes a long way), I was more than a little nervous about using a product priced at $55 per 30 milliliters. But I was pleasantly surprised when I found that the recommended two drops really were enough to cover my entire face. What’s more, the gel goes on supersmooth and delivers impressive and immediate results. Not only does it moisturize the skin itself; it maximizes the effectiveness of other hydrating products by binding water to the skin’s surface (hyaluronic acid, one of the product’s key ingredients, can reportedly soak up more than 1,000 times its own weight in water). Vitamin B5 repairs damaged tissue and replenishes essential nutrients to help skin appear plumper and younger. And because it’s oil-free, the gel can be used on any and all skin types, a selling point that will appeal to everyone in your inner circle and beyond. —Janelle Harris