Audioscrobbler (www.audioscrobbler.com) is the brainchild of university student Richard Jones, better known as RJ. It started as his Computer Science degree project at the University of Southampton and is constantly evolving.
The Audioscrobbler Project is an ongoing exploration into
Social Information Filtering, music being the "Problem Domain".
You basically just load a plugin into your preferred player, currently plugins are for Winamp 2 and 3, XMMS and iTunes. You listen to your songs, and they are submitted to Audioscrobbler. There they help give you a profile of your musical preferences, but also help others in discovering new music thanks to your submission.
Taken from the Audioscrobbler website, www.audioscrobbler.com :
"In a nutshell, Audioscrobbler endeavours to be your personal music advisor. It grows to know what music you like by monitoring what songs you play on your computer. From this information you can discover other users that share some or all of your taste in music. You can also view data showing what your most-played artists are, and find out who likes a particular artist the most. Basically The Audioscrobbler Project is turning into a fantastic way of discovering new music, and discovering people who like the
same music as you. When you have listened to 500 songs, Audioscrobbler will begin to match you with other users that have a similar taste in music to you. A list of "similar users" will then appear on your personal stats page."
Currently the project has approximately 3000 users, with an increasing userbase. Audioscrobbler had to change servers twice, because of an increased amount users, and being featured on Slashdot twice. BBC featured a story about Audioscrobbler, which boosted the userbase with approximately 400 users
Challenges include proper tagging of music. Audioscrobbler is currently attempting to implement the MusicBrainz system to recognize songs by looking at bad tags, song length and path.
The project currently needs users who listen to rare/eccentric/weird music, to better feature a wide range of artists.
Try it, it's pretty darn cool.