Janus Friis and Niklas Zennström are two of the most popular entrepreneurs as they started KaZaa, Skype, and Joost. Their latest venture is a Twitter-like digital music service called Rdio.com.
Rdio offers users access to 5 million tracks through all the major labels to people in the U.S. and Canada. Rdio is available for free for three days and then charges $5 for web only services or $10 for web plus mobile. Rdio competes directly with Rhapsody and Napster. Rdio will show users what their friends are listening to and what they like through real-time feeds. The service is currently invite-only.