Who Wants to Live Forever?"Millions long for immortality who don't know what to do with themselves on a rainy Sunday afternoon," wrote British novelist Susan Ertz. So it would seem that humankind was never designed-emotionally or spiritually, let alone biologically-for long, productive lives. But new, life-extending technologies based on advanced genetics and stem-cell reprogramming are coming at us anyway.Construction magnate John Praxis topples...