I've created a package "moz-controller" (https://github.com/RenWenshan/emacs-moz-controller), which allows you to control Firefox from Emacs. It could be useful when you are hacking and reading web pages at the same time.

This is the first package I've ever written, any feedback are welcome.

EDITED 2014 Jun 1st 10:40 PM:  It's now available on melpa.
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