Database technology can work to help us find new music, events, and people. Last.fm is among the most popular new-edge programs that merge Internet radio with music recommendation services. Most of the site is free, but as usual a couple perks come with spending less than $10 a month, mostly intel for the heavy researcher.
A user signs-up by installing an application on their computer that records what music that user is playing. Then, through the process of collaborative filtering, it finds similar users and genres for the user. They call it scrobbling.
Last.fm's 'about us' section couldn't say it better:
Last.fm 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.You will meet people based on how their taste relates to your own or to whatever you search for. I tried tripping up the system with the most obscure artists I could think of, but I got several recommendations hitting the bullseye every time.