rtorrent
rtorrent is very useful if you want to download files in a shell. See e.g. tmux for a very useful scenario.
The basic use of rtorrent is very simple. Start rtorrent either with or without torrent files.
rtorrent [file/URL ...]
If you haven't supplied any torrent files at start up you can open a torrent file by pressing ENTER.
Inside rtorrent you may use UP/DN arrow keys to move between torrents. Use LE/RT arrow keys to get more information about a torrent.
Ctrl-qQuit applicationCtrl-sStart download. Runs hash first unless already done.Ctrl-dStop an active download or remove a stopped downloadCtrl-kStop and close the files of an active download.Ctrl-rInitiate hash check of torrent. Starts downloading if file is not available.
Magnet links works fine in rtorrent 0.8.9 or later.