Torrent File Editor - Qt based GUI tool designed to create and edit .torrent files.
dottorrent-gui - An advanced GUI torrent file creator with batch functionality, powered by PyQt and dottorrent.
PicoTorrent - PicoTorrent is designed to be a tiny, easy-to-use BitTorrent client with low memory usage.
Android Torrent Client - Android Torrent Client. Open Source. GPLv3
Bitford - BitTorrent client for Chrome that can stream videos while they're being downloaded
qBittorrent - Lightweight and open source torrent client that runs on all major platforms.