|Why They're Hot:
Men who buy items like Gucci shirts are accustomed to attentive service in the stores they shop. MrPorter.com attempts to provide that same type of experience online, offering magazine articles about men's fashion and style advice delivered in a sophisticated, wry voice. Product pages include detailed photos, down to the buttons on a blazer sleeve, plus information about size and garment care. MrPorter.com, part of the Net-A-Porter Group, offers free delivery and returns, including same-day delivery in New York and London. Not that Mr. Porter turns down his nose at others; the site offers express delivery to 170 countries. And it recognizes where a customer is coming from. A U.S. visitor, for instance, sees on every page the notation "Free shipping on all US orders," and prices in U.S. dollars.