Tom Waits, even with his barnyard growl and urban hipster yawp, may just be what the "Daily Telegraph" calls him: the greatest entertainer on Planet Earth. Over a span of almost four decades, he has transformed his music and persona not to suit the times but his whims. But along with Bob Dylan, he stands as one of the last elder statesmen still capable of putting out music that matters. Journalists intent upon cracking the code are more likely to come out of a Waits interview with anecdotes about the weather, insects, or medieval medicine. He is, in essence, the teacher we wished we had,...