If there's one thing Hollywood has mastered, it's finding shortcuts to great skin - and lately, that shortcut looks a lot like a glowing red LED mask. Once reserved for dermatologists' offices and high-tech clinics, red light therapy has quietly become the at-home ritual of some of the industry's most famously youthful faces. Jennifer Aniston has long credited it as part of her skin-maintenance routine, while Rita Ora has also joined the growing list of celebrities turning to red light masks to keep their complexions smooth, firm and camera-ready.