Emacs behind http proxy

Question

Emacs is able to access the internet with packages such as url.el or the W3 web browser.

Also, the Emacs Lisp Package Archive is heavily dependant on package url.el.

Now, how do I configure Emacs to use my HTTP proxy to connect to the internet in general ?

Bonus points for any help with ELPA behind a proxy.

Yes, I've had problems with HTTP proxies before.

Answer 1

For w3m, this setting has worked for me:

(setq url-proxy-services '(("no_proxy" . "work\\.com")
                           ("http" . "proxy.work.com:911")))