We all know sex sells. But the last couple of weeks have offered a few glimpses of just how and where it's selling — and where it isn't — in our Internet era. For example, Ashley Madison, a dating website for people who want to cheat on their spouses, is preparing for an initial public offering on the London Stock Exchange. Strip club operator RCI Hospitality Holdings (RICK) recently reported record sales, while lingerie chain Frederick's of Hollywood and many pornography sites continue to struggle amidst fierce competition and rampant piracy. Ashley Madison has 36 million members in 46 countries and generated $115 ... (full story)