"If anyone young is reading this, go, right this minute, put on a bikini and don't take it off until you're 34." This is Nora Ephron, reminding us that now--right now--is the peak naked moment of our lives, the highest point on a steep slope of sagging. I remembered this rule when my email dinged with a dinner invitation. The invite contained details about the host (a friend of a friend), the cuisine (Indian) and the attire (none). A nude dinner party.