'A man sits in his car at the traffic lights, waiting for them to go green...' Heaven, the Book of Revelation tells us, is a city of pure gold, 1,500 miles high, and decorated in sapphire, amethyst, and emerald. According to the Koran, it is peopled with immortal youths and bashful virgins, and there are jeweled couches on which to recline and enjoy food and drink. But wouldn't most of us feel a little out of our element in such a place? What...