Games Workshop has added three new U.S. locations as of the end of October, for a total of 50.  The new Hobby Centers are near San Francisco (at the Sun Valley Mall), near Boston (Natick Mall) and on Third Avenue in New York City.  Games Workshop has expanded from one Hobby Center to 50 over the last seven years in America, with three more planned by year's end in Atlanta, St. Louis and another unspecified location.  The company expects to double the number of Hobby Centers to 100 within two years.  Worldwide, Games Workshop owns nearly 300 retail stores.