In the following video Voddie Baucham provides a remarkable and helpful theodicy:
His answer may not be philosophically rigorous, but it is helpful to refocus people on the important points. I must say that it is not an answer that had occurred to me previously, as a response to the question, "If God is so good, why does evil exist?" ... though perhaps it ought to have.
H.T. to the Truth Matter blog for bringing this to my attention (link).