In the new trend among high-end hotels, men need not apply. The ritzy Dukes in London is the latest to experiment with women-only rooms, notes Katy Holland at Aol. The idea is to cater to single females or women traveling in groups, and the no-boys-allowed rule applies even to the hotel staff that caters to the rooms. The Naumi in Singapore and Premier in New York City have similar offers, though a Denmark government agency recently ordered the Bella Sky in Copenhagen to stop offering women-only floors. (More hotels stories.)