Billionaire hedge fund manager Ken Griffin is really moving up in the world these days, literally as well as figuratively. Griffin's Citadel announced earlier this week that the ultra-successful hedge fund firm was leasing out 200,000 square feet (including the penthouse) of a new luxury office building in Manhattan. The new luxury office tower will be located at 425 Park Avenue in Manhattan. The building will take up the entire block between East 55th and East 56th Streets and will top out at around 900 feet. Take a deep breath -- Citadel has agreed to pay a record $300 per square foot in rent, in a lease deal that includes the buildings ultra-lux penthouse. This move to a... More