Drakma
Drakma is a fully-featured Common Lisp HTTP client library that knows how to handle HTTP/1.1 chunking, persistent connections, re-usable sockets, SSL, continuable uploads, cookies, and other things.

It was developed on LispWorks, but can be used with several other Common Lisp implementations as well.

It's written by Edi Weitz and can be found at http://weitz.de/drakma/.

ASDF-install package (obsolete) http://weitz.de/files/drakma.tar.gz