There's been a huge amount of material on manic-depression (especially the latter phase recently), based on recent research--most of which can be found via the previously mentioned posts. Two pop works that explore the state (not really "madness" in any technical sense, I believe) are William Styron's book on his own bout with depression (the title is something like "Darkness of Night") and "Listening to Prozac," which explores questions raised by the most popular treatment for the condition. (There's also a newer book that answers that called something like "Talking Back to Prozac"). --Don Larsson, Mankato State U., MN