US Department of Energy
U.s. Department of Energy: Fuel Cell Technologies Program: Fuel Cell Animation
A series of animated illustrations show how a polymer electrolyte membrane fuel cell works. PEM fuel cells are the most common type used in flex-fuel vehicles.
Other
Mit Technology Review: Tomorrow's Cars
A collection of articles about innovations in automotive technology. Titles include: Prying Open the Prius, Cheaper Fuel Cells, Better than Hybrids, and Free Power for Cars.