Solar panels and photosynthesis. 8 minutes.
Dirac equation predicted the existence of antiparticles, such as positrons that could be understood as 'holes' in the Dirac sea. The condensed matter analogy is the hole in the Fermi sea. Solar panels work by absorbing photons that create particle-hole-excitations (called excitons). Also (the first steps of) photosynthesis have the same idea.