elbo.ws is an online feed aggregator that aggregates music blogs exclusively. It detects links to mp3

MP3

MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is a patented digital audio encoding format using a form of lossy data compression...

 files and then extracts the id3

ID3

ID3 is a metadata container most often used in conjunction with the MP3 audio file format. It allows information such as the title, artist, album, track number, and other information about the file to be stored in the file itself....

 tags from the mp3 files.

elbo.ws uses this data to allow users to search through all the blogs and links to mp3 files are checked routinely to ensure they are still active. The site also compiles charts of how many times artists and tracks are linked to in order to gauge an idea of the band's popularity in the blogosphere

Blogosphere

The blogosphere is made up of all blogs and their interconnections. The term implies that blogs exist together as a connected community or as a social network in which everyday authors can publish their opinions...

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