I have added Bittorrent capabilities to Pike, under Protocols.Bittorrent. There is also an example of a tiny agent (what's it called - it's not really a client).

Enjoy. :)

I have a more elaborate downloader then the example in http://www.mirar.org/btdownload.pike.txt mostly containing of prettyprinting to a vt100(xterm)-like terminal of the current status (*lots* of flashing stuff).