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Who would have thought that listening to tunes in the lonely confines of one's home could be social? From a crew of internet music scenesters – with such job titles as "Streaming Genius (Ministry of Radio)" and "Features Ninja (Web Awesomeness Unit)" -- comes Last.fm: a social networking website, music recommendation system, and internet radio station that logs every song played on a network member's computer. According to Last.fm, the website "taps the wisdom of the crowds, leveraging each user's musical profile to make personalised recommendations, connect users who share similar tastes, provide custom radio streams, and much more."

More than ten million times a day, Last.fm users log their music listening habits to Last.fm servers, helping to collectively build a gargantuan music listening habits database (at the time of this writing 3,856,592,987 songs have been logged in the website's database). This information is then used to construct a profile of each user's musical preferences, and these profiles are in turn used to dynamically create personalized "recommended radio" stations that can be listened to, at will, for free. Last.fm also helps audiophiles discover new musicians (based on demonstrated listening habits) and generates a variety of real-time music charts that can be posted to a blog, or a social networking website such as MySpace, LiveJournal, or Facebook. Whether Last.fm is rebel radio or another chance for big brother to read our minds, it's worth checking out.