Undoubtedly many of you know of it already, but Transmission (http://www.transmissionbt.com/) is an amazing, lightweight Bittorrent client which includes a web interface and things like scheduling. It's included by default in many Linux distros.
-Chrome plugin on my main computer + webUI on other computers (or for additional commands)
-Transdroid Android client on my Nexus phone and tablet
Almost perfect (almost because sometimes there are some minor glitches)