Audioscrobbler Plugin
Last.fm can optionally build a profile directly from a user's music played on their personal computer. Users must download and install a plugin for their music player, which will automatically submit the artist and title of the song after either half the song or the first four minutes have played, whichever comes first. When the track is shorter than 30 seconds (31 seconds in iTunes) or the track lacks metadata (ID3, CDDB, etc.), the track is not submitted. To accommodate dial-up users, caching of the data and submitting it in bulk is also possible.
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