MozRepl
Notice
MozRepl is looking for a maintainer. Please get in touch with hyperstruct [at] gmail.com
or luca.greco [at] alcacoop.it
.
What is it
MozRepl is an extension for Firefox and other Mozilla applications. It listens on a TCP port for connections (by default localhost only) and responds with a shell where you can evaluate JavaScript code, in the browser context as well as in web pages.
Demo
http://www.youtube.com/watch?v=5RSnHN6S52c