BitTorrent Partial Download File
Bit Torrent is a file transfer technology, it breaks files down in to parts which are then downloaded from various sources, once a user starts downloading a torrent he will also automatically upload the file so that others are able to download it. Bit Torrent clients are usually able to resume stopped or paused downloads, to do this they use temporary file that have the .bt! file extension.
» Bit Torrent
How to open .bt! files?
Software to open .bt! files
What are .bt! files