from http://voiture-jaune.tumblr.com/
http://en.wikipedia.org/wiki/Alexander_Calder has a brief but unenlightening description, and doesn't hit the innovative genius key that a documentary I watched did. Alexander Calder had a roll of wire in his pocket and a pair of pliers, and when inspiration hit he would create, anywhere and anytime, and made masterpieces like this circus of minitures
For a gallery of Alex in his studio: http://lecontainer.blogspot.com/2010/06/calder-in-his-studio-dav.html