A planet money podcast from a few years ago on the kilogram: http://www.npr.org/templates/story/story.php?storyId=112003322 http://www.npr.org/templates/story/

A planet money podcast from a few years ago on the kilogram: http://www.npr.org/templates/story/story.php?storyId=112003322 http://www.npr.org/templates/story/story.php?storyId=1120033...