Sleep scientists agree: Sunlight affects your internal clock. More specifically, that morning light pouring in through the window actually helps you wake up. If dark winters, cloudy weather, or a low-light room are keeping you from rising refreshed, the Philips Wake-Up Light may provide just the right dose of almost-natural light needed to rouse you from your slumber. Here's how it works: 20 to 40 minutes before wake-up time, the light turns on—getting gradually brighter until your room is bathed in sun-simulating light. You wake up not only more naturally, but more energized as well. Available at Amazon; $132.