LifeHacker makes a strong recommendation for Mr Beams lights:

"Mr. Beams Motion Sensing LEDs light up any room or closet without wires, screws, or hassle. Seldom do new apartments come with enough lighting built in. If you need a bit more light in certain corners of your home, the Mr. Beams motion sensing LEDs are a great solution. Mr. Beams is a line of super-convenient wall lights that can light up pretty much any portion of your house..."
 

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