InBflat.net features 20 YouTube videos of people playing instruments in the key of B flat. inbflat.net hide caption

itoggle caption inbflat.net

Companies offer services as varied as song streaming, concert ticket sales and music downloads using business models ranging from subscription to free-if-you-watch-an-ad. Courtesy of Pandora, Songkick, Rdio, Rhapsody, eMusic and Spotify hide caption

itoggle caption Courtesy of Pandora, Songkick, Rdio, Rhapsody, eMusic and Spotify

The Consumer Electronics Show this week is expected to feature more tablets to compete with the Apple iPad, left, and Samsung Galaxy Tab, right. Gero Breloer/AP hide caption

itoggle caption Gero Breloer/AP

Even though Facebook remains wildly popular, a number of startup social networks are trying to woo people with the promise of better privacy controls. Nicholas Kamm/AFP hide caption

itoggle caption Nicholas Kamm/AFP