BBC Horizon - Dangerous Knowledge (http://www.youtube.com/view_play_list?p=CACA0E97E3FD3BB5)
In this one-off documentary, David Malone looks at four brilliant mathematicians - Georg Cantor, Ludwig Boltzmann, Kurt Gödel and Alan Turing - whose genius has profoundly affected us, but which tragically drove them insane and eventually led to them all committing suicide.