Airbnb

= using the Internet to help people rent out a room, or even a couch, to frugal travelers

History

"after receiving funding as well as mentoring from incubator Y Combinator in 2009, the startup exploded. Airbnb -- the name was originally Airbed and Breakfast in a reference to the use of airbeds for guests -- has listings in 16,000 cities around the world and has booked more than two million nights." (http://knowledge.wharton.upenn.edu/arabic/article.cfm?articleid=2714)