"Even though I have dozens of serums in my medicine cabinet, I've never found one that combines all my wishlist ingredients. . . until now. With the Skinceuticals Custom D.O.S.E. Serum ($195), a custom serum from Skinceuticals, I was able to work with my derm to create my dream formula (think retinol and hyaluronic acid and brightening ingredients). While it's pricey, and you can only get it in a doctor's office, customized skin care is a huge trend right now, and I have a feeling we're going to be seeing a lot more of this serum soon." — DD