Since the long steep plunge of 2008, the Dow Jones Industrial Average has been confidently on the rise for over a year, gaining more than 60 percent since its lows. The top banks in trouble just two years ago are this year posting record profits. To celebrate this financial exuberance, enter the Setai: a 31-story luxury condominium tower complete with lavish spa, optional butler and maid service, and a Michelin-rated restaurant inside a former office building at 40 Broad Street.