Would like to mention SS Plex[1]. It doesn't use torrents, nor XBMC really, but it allows you to stream and download content to a wider variety of devices.
I say "wider variety" because Plex runs on everything XBMC runs on (via PleXBMC), and transcodes files into a format the client supports.
I've recently switched from XBMC on a hacked ATV1 to Plex on a MacMini and been really happy with it so far. Having the Plex app on my Samsung TV and then on iPhone and iPad is a great bonus meaning it's trivial to pick up where I left off.
I always thought the "keep watching from a different device" thing was such a gimmick, but I'll go from watching a movie on the TV, then to watching a few minutes more in bed before sleeping then another few minutes over breakfast.
If my 18mo old is lazing in bed with us, I can pull up a TV show he likes, give him some headphones and snooze for a bit longer.
Would like to mention SS Plex[1]. It doesn't use torrents, nor XBMC really, but it allows you to stream and download content to a wider variety of devices.
I say "wider variety" because Plex runs on everything XBMC runs on (via PleXBMC), and transcodes files into a format the client supports.
[1]: http://mikew.github.io/ss-plex.bundle/