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).