(Portland, OR)  --  Portland is being called one of the top 10 "Most Fun" cities in the U.S.  That's according to a new study from WalletHub, which lists Portland as America's 9th most fun city.  WalletHub looked at more than 180 U.S. cities, analyzing factors like fitness clubs per capita, movie prices and open hours of breweries.  Las Vegas came in first place.