One of the most common ways to turn the sun's energy into electricity is by persuading silicon to give up some of its electrons. But it's also quite expensive, so any innovation that helps reduce the cost of solar cell production is welcome. Researchers in Israel have come up with a cell that uses only 20% of the silicon in a standard cell yet yields similar amounts of electricity. It does this by diffusing any light that falls on its surface and sends it off to photovoltaic collector strips on each of its sides. And it doesn't even need bright sunlight to operate.