[clappski]

Deluge is pretty good, that's what I tend to go for.

[voltagex_]

I like Deluge, but I really wish its default API (protocol) wasn't so difficult to use. It's bencoded Python objects as far as I can tell. If you've never heard of bencoding, that's because it's only used by Deluge.

[mappu]

The .torrent file format itself uses bencoded fields.

[voltagex_]

Ah crap. I meant rencoded. https://github.com/aresch/rencode