Increasing insecurity about the fossil energy supply and environmental changes force us to intensify the search for clean alternative energy sources (e.g., the sun). Here, we show that the photonic crystal structure of dentin, already exploited to treat tooth inflammations, inspires a practical method to harvest sunlight. Arrays of toothlike structures mounted on silicon permit collection of sunlight virtually independent of the angle of incidence of the sun, which could be vital, for instance, in Antarctica.