3.

Where They're Based: Bay Area

What they do: Dropbox allows you to synch and share your files online. One of the upsides to the service is that any change or update you make to a file, it is updated across all your devices that access it. It also has good version control, allowing you to "undelete" files.

Quote from founder Drew Houston: (Referencing Dropbox's sophisticated version control): "It's almost like a time machine that works across all platforms."

Where they got funding: $15,000 from Y Combinator. They later received funding from Sequoia Capital.