Pity the companies with expatriate employees in Asia. A study released last month by the Corporate Resources Group of William M. Mercer Cos. LLC found that Tokyo, Hong Kong, Beijing, Osaka, and Shanghai have the highest cost of living among cities worldwide. In fact, the only non-Asian cities in the top 10 are London and Moscow. Tokyo is 65.5 index points above New York City -- the base of the index at 100 points. The most expensive city in different countries with their index rating in parenthesis: Toronto (68.1); Buenos Aires, Argentina (97.6); Cairo, Egypt (97.3); Sydney, Australia (68.4), and Geneva (107.5). The least expensive city in the U.S. to do business: Portland, Oreg., with an index cost of 66.1, followed by Winston-Salem, N.C. (67.2) and Cleveland (67.5).