lurb is a utility for testing BitTorrent clients.
Useful if you want to check your port-forwarding or similar, or just to send arbitrary handshakes and see if a peer has a torrent.
With npm:
npm i -g lurb
lurb handshake -h 127.0.0.1 -p 6969 -i ab6ad7ff24b5ed3a61352a1f1a7811a8c3cc6dde
Thanks to Bram Cohen for the initial BitTorrent specification, and Arvid Norberg for his amazing work on libtorrent.
Also thanks to gl0ryus for suggesting the name of this project.