Mega Millions Up to $640M

Mega Millions is up to $640 million, and there's still about six hours to go before the numbers are drawn. Officials figure Americans will have plunked down nearly $1.5 billion by tonight's 11pm drawing, reports AP. "This is unprecedented," says a lottery spokeswoman. Exhibit A of the frenzy: A cafe worker in Arizona says one buyer went home with $2,600 worth of tickets. Everyone's trotting out lightning-strike analogies to explain why you won't win, but just in case ... here's some advice. (More Mega Millions stories.)