A long time ago, I suggested rtorrent was something like an “rtorrent daemon.” That’s still true, of course — I don’t know of any torrent client that runs lighter and has the same range of controls as rtorrent.
I never really tried to set it up as a true daemon though, until I saw this thread on the Arch Linux forums, and its corresponding wiki page. It might not sound like it’s worth the effort, but it’s kind of nice to run the entire system in the background, unattended and preconfigured, and just drop torrents and run.
Mimicking the same concept in Crux was fairly easy; I needed to add a user called rtorrent, set up the proper subdirectories and then configure rtorrent’s rc file as I liked. The script shown in the thread and on the wiki needed scraped down a little bit, to where it’s really just a simple series of start and stop commands. (Oh, and the daemon needs either screen or dtach, depending on which you prefer.)
I don’t know if I’d go through the work of setting this up every time I wanted to install rtorrent, but I can see where this would be useful on a remote machine, or on a machine that sits by itself and does nothing but download. Oh wait, that was my original point, wasn’t it?