AirBNB.com offers a money-saving alternative to book your stay when you want something more than just a hotel room.

The service has come out of nowhere to have booked 10 million guest nights. The funny thing is they came to the game late, after sites like VRBO.com and HomeAway.com had already established a similar niche. All three sites let owners of properties rent their condos, homes or apartments in competition with traditional hotel rooms.

It just goes to show that being the first in the Internet world doesn't necessarily mean you win. AirBNB now has 200,000 listed properties around the world.

On the other side of the coin, people who can't sell their properties are putting them up on AirBNB and making some real money.

My senior producer Kim stayed in an Italian AirBNB property in March during our annual winter meeting. The place was about $90 a night and she got an entire apartment rather than just a room, located in an area that many tourists don't get to stay in.

If you want to book a stay through AirBNB, look at properties that have lot of reviews. And you must have a credit card for booking because you pay AirBNB as the middle man, not the individual owner you're renting from.

If you're looking at listing your property, know that the insurance issue has been the great unknown. AirBNB now offers owners $1 million in coverage when they put a property up for rent, but your own insurer might kick you to curb if they find out about what you're doing!

The number of complaints I've received about AirBNB has been relatively small. In New York, people are griping about the transient and exuberant nature of AirBNB guests. Some cities elsewhere want hotel and motel taxes collected. So there are some growing pains with this business model.

But it can be a great opportunity to get more than just a hotel room, or for a wannabe landlord to get significant income.