For many women one of the pleasures of ageing is that it frees them from the need to continually monitor and police their appearance. What a relief: bring on the elasticated waistbands and sensible shoes, they cry! But if 50 is the new 30, 60 the new 40, etc etc, they're doomed to eternal self-scrutiny. How to look hot at 100? The very prospect gives them a migraine.