Remember Kazaa? One of the first file-sharing programs on the Web? It was sued by record companies for settled for millions of dollars. But it's coming back. Sort of.

Kazaa co-founders Niklas Zennström and Janus Friis (they also co-founded Skype) are teaming up to launch Rdio, an online social music service that will work on the Web and on smartphones.

The service will allow users who pay the full amount to share their music tastes with friends, and stream and store songs on certain mobile devices, like the iPhone and BlackBerry. The start-up will charge $5-10 a month for unlimited access to a large catalog of music. It is similar to other music subscription services, like Rhapsody.

From the Rdio blog:

Rdio takes the work out of finding and choosing what to play next -- you can follow friends and other people with great taste in music, get inspired by what they're playing, and listen to their playlists. You don't have to sit and stare at an empty search field, trying to think of what to play.

We've got music from labels large and small, majors as well as indies -- they're listed on our Content Partners page. We're constantly adding more music, so if you don't see something you're looking for, it'll probably appear soon.

The site is currently in an invitation-only period and will become more widely available later this year.

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Follow Daryl Paranada at @darylparanada