RTorrent

RTorrent is a highly configurable torrent client based on libtorrent and ncurses.

Installation
RTorrent is available in portage. A quick note on the USE flags before emerging:

Configuration
The RTorrent configuration is stored in the user's ~/.rtorrent.rc. A lot can be configured, for this reason, the configuration is divided in sections.

Basics
These options are pretty straightforward:

Watching a Directory
You can configure RTorrent to watch one or more directories for new torrent files and queue them automatically. You can also set a download directory for each watch directory (rather than downloading to the default download directory).

Ratio Handling
You can control seed time by making it dependent on each torrent's ratio. Each torrent is seeded for a minimum of min.set percent. if a total of upload.set has been uploaded. If upload.set is not reached, it will seed a maximum of max.set percent. Read the wiki on the libtorrent site for different ratio groups.