"Chicken feathers!!! Yes, don't laugh! Chicken feathers are pure keratin... protein. The poultry industry has to get rid of thousands of tons of chicken feathers every year. You heat the up to 200ºC which ossifys them and partially 'crystalizes' them. Then, you heat them up to 400ºC and you have a compound with zillions of area/surface for attaching hydrogen atoms in an efficiency that beats nanotubes by many, many factors. This recently discovered technique could speed up the use of hydrogen as a practical energy source sooner than expected."