"Old is the new new" in this exuberant exploration of ideas and innovation. Guardian columnist Steven Poole celebrates the advances made when we resurrect, reconsider, revise - rethink - old theories and concepts that floundered or fell out of favor. From electric cars (the first was built in 1837) to medicinal leeches (which are now FDA approved for skin grafts and body part reattachment operations), many modern marvels have long, twisty histories. What fun for creative minds!