What.cd

What.cd is a private Bittorrent tracker that probably has music on it, but nobody knows since none have ever managed to get an invite. The invites are notorious for having trouble sending, as hundreds of people can kindly send one anon an invite without one getting though to the user who asked for one.

The Interview
There is an interview process for people who fail to get invited (that's you!) that actually isn't that hard. Going to this website will give a potential user all of the information he/she needs to get into the site, which includes a basic knowledge of lossy and lossless formats, transcodes, and what exactly is acceptable on the site.

The Site
What.cd has a huge library of music on it, because everyone is so desperate to get upload credit that they resort to uploading the most obscure Bandcamp releases and rare records they can find just to keep their pathetic ratios going. All of the music (with a few exceptions) is in a standard format, either FLAC or MP3 in most cases.

What.cd also has an active forums and community, and they talk about music a bunch, but they're insufferably kind and the discussion is awful.