Torrent Trader Lite:

Torrent Trader Lite is a Bittorrent Tracker that requires only php to work ! Very easy to use, it will help you to setup a bittorrent tracker on your website.
This is my latest open-source script. If you want to start using Bittorrent, then this is the way to go !
You can also check here if you want a tracker with more features.

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