From the April 2011 issue of Entrepreneur

Believe it: Airbnb can make business travel more fun. Launched in the summer of 2008 by three couch-surfing-inspired twentysomethings, the San Francisco startup has grown from a site featuring a mere 40 listings in New York City into a massive online property-rental network populated with more than 40,000 privately listed locations around the world, from dorm-like shared bedrooms to igloos and entire castles. That's right, castles.

According to co-founder, CTO and host Nathan Blecharczyk, Airbnb's main target is the casual traveler, but more and more business travelers are booking, some simply out of boredom. "I had a frequent traveler to the Bay Area stay with me because he's been in every hotel in the area and wanted to change it up," Blecharczyk says. "Now he's trying every place on Airbnb that meets his criteria."

Also, younger business travelers are after a "more authentic, cooler" experience, often preferring to book a downtown apartment or condo where they can entertain friends and guests. And for people looking for internship- or project-length sublets, Airbnb has introduced monthly pricing schemes, eliminating the creep factor of Craigslist's temporary housing board. The reverse option is popular, too, for business travelers to monetize their empty spaces.

Airbnb is still a young company, but revenues and listings grew by a staggering 800 percent in 2010.

"We have 5,000 properties in New York City, so it's like there's a property on every block, and literally something for every expectation and use," Blecharczyk says, adding that the site is building similar depth in urban areas like Los Angeles, Washington, D.C., London and Berlin, among some 8,000 other cities. The reason for that is the company makes transactions simple. Listing is free and easy for hosts, and for guests the site offers a refund guarantee, trustworthy reviews (only people who stay can leave comments in the system) and cool accommodations that aren't available anywhere else, including a private island owned by a native Fijian renting for just a few hundred dollars a night (it's been in the family for generations).

Entrepreneur gave the service a spin during a recent stay in New York City, where hotel rates are--like most everything else--painfully high. We searched for properties near Times Square and, based on a combination of user reviews and amenity descriptions, settled on a smartly decorated railroad-style apartment in the Hell's Kitchen area, featuring a fully furnished, 350-square-foot room with organic bamboo hardwood floor, free Wi-Fi, towels and linens, a private entrance, a small backyard and kitchen privileges.

There were inconveniences: the shared bathroom, the need for an e-mail exchange that caused a delayed confirmation (though hosts can opt-in for the Instant Book option) and the hassle of getting the key. The upside, however, was great: flexibility in scheduling, getting to do some online shopping, a fantastic rate of $125 per night (plus a moderate service fee)--and we made a new friend.

Our recommendation? Make it interesting and ditch the hotel, unless your idea of a good time is watching cable until you pass out on one of your two double beds.